diff --git a/HTMLKit/HTMLCharacterToken.h b/HTMLKit/HTMLCharacterToken.h
index be3d4ee..0341991 100644
--- a/HTMLKit/HTMLCharacterToken.h
+++ b/HTMLKit/HTMLCharacterToken.h
@@ -16,10 +16,12 @@
 - (instancetype)initWithString:(NSString *)string;
 
 - (void)appendString:(NSString *)string;
-
 - (BOOL)isWhitespaceToken;
-- (HTMLCharacterToken *)tokenByRetainingLeadingWhitespace;
-- (HTMLCharacterToken *)tokenByTrimmingLeadingWhitespace;
-- (HTMLCharacterToken *)tokenByTrimmingFormIndex:(NSUInteger)index;
+- (BOOL)isEmpty;
+
+- (void)retainLeadingWhitespace;
+- (void)trimLeadingWhitespace;
+- (void)trimFormIndex:(NSUInteger)index;
+- (HTMLCharacterToken *)tokenBySplitingLeadingWhiteSpace;
 
 @end
diff --git a/HTMLKit/HTMLCharacterToken.m b/HTMLKit/HTMLCharacterToken.m
index 2548558..1425778 100644
--- a/HTMLKit/HTMLCharacterToken.m
+++ b/HTMLKit/HTMLCharacterToken.m
@@ -39,31 +39,44 @@
 	return [_characters isHTMLWhitespaceString];
 }
 
-- (HTMLCharacterToken *)tokenByRetainingLeadingWhitespace
+- (BOOL)isEmpty
+{
+	return _characters.length == 0;
+}
+
+- (void)retainLeadingWhitespace
+{
+	NSUInteger index = _characters.leadingWhitespaceLength;
+	if (index > 0) {
+		[_characters setString:[_characters substringToIndex:index]];
+	}
+}
+
+- (void)trimLeadingWhitespace
+{
+	NSUInteger index = _characters.leadingWhitespaceLength;
+	if (index > 0) {
+		[_characters setString:[_characters substringFromIndex:index]];
+	}
+}
+
+- (void)trimFormIndex:(NSUInteger)index
+{
+	[_characters setString:[_characters substringFromIndex:index]];
+}
+
+- (HTMLCharacterToken *)tokenBySplitingLeadingWhiteSpace
 {
 	NSUInteger index = _characters.leadingWhitespaceLength;
 	if (index > 0) {
 		NSString *leading = [_characters substringToIndex:index];
+		[_characters setString:[_characters substringFromIndex:index]];
 		return [[HTMLCharacterToken alloc] initWithString:leading];
 	}
-	return nil;
-}
 
-- (HTMLCharacterToken *)tokenByTrimmingLeadingWhitespace
-{
-	NSUInteger index = _characters.leadingWhitespaceLength;
-	if (index < _characters.length) {
-		NSString *remaining = [_characters substringFromIndex:index];
-		return [[HTMLCharacterToken alloc] initWithString:remaining];
-	}
 	return nil;
 }
 
-- (HTMLCharacterToken *)tokenByTrimmingFormIndex:(NSUInteger)index
-{
-	return [[HTMLCharacterToken alloc] initWithString:[_characters substringFromIndex:index]];
-}
-
 #pragma mark - NSObject
 
 - (BOOL)isEqual:(id)other
diff --git a/HTMLKit/HTMLParser.m b/HTMLKit/HTMLParser.m
index 4b9b8db..5a28b5d 100644
--- a/HTMLKit/HTMLParser.m
+++ b/HTMLKit/HTMLParser.m
@@ -253,7 +253,7 @@
 				if (characters.length <= 1) {
 					return;
 				}
-				token = [token.asCharacterToken tokenByTrimmingFormIndex:1];
+				[token.asCharacterToken trimFormIndex:1];
 			}
 		}
 	}
@@ -713,10 +713,14 @@
 {
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
-			if ([token.asCharacterToken isWhitespaceToken]) {
+		{
+			[token.asCharacterToken trimLeadingWhitespace];
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
+		}
 		case HTMLTokenTypeComment:
 			[self insertComment:token.asCommentToken asChildOfNode:_document];
 			 return;
@@ -761,10 +765,14 @@
 			[self insertComment:token.asCommentToken asChildOfNode:_document];
 			return;
 		case HTMLTokenTypeCharacter:
-			if ([token.asCharacterToken isWhitespaceToken]) {
+		{
+			[token.asCharacterToken trimLeadingWhitespace];
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
+		}
 		case HTMLTokenTypeStartTag:
 			if ([token.asStartTagToken.tagName isEqualToString:@"html"]) {
 				HTMLElement *html = [self createElementForToken:token.asTagToken inNamespace:HTMLNamespaceHTML];
@@ -795,10 +803,14 @@
 {
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
-			if ([token.asCharacterToken isWhitespaceToken]) {
+		{
+			[token.asCharacterToken trimLeadingWhitespace];
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
+		}
 		case HTMLTokenTypeComment:
 			[self insertComment:token.asCommentToken];
 			return;
@@ -838,11 +850,12 @@
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
 		{
-			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenByRetainingLeadingWhitespace];
+			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenBySplitingLeadingWhiteSpace];
 			if (leadingWhiteSpace) {
 				[self insertCharacters:leadingWhiteSpace.characters];
 			}
-			if ([token.asCharacterToken isWhitespaceToken]) {
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
@@ -955,11 +968,12 @@
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
 		{
-			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenByRetainingLeadingWhitespace];
+			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenBySplitingLeadingWhiteSpace];
 			if (leadingWhiteSpace) {
 				[self insertCharacters:leadingWhiteSpace.characters];
 			}
-			if ([token.asCharacterToken isWhitespaceToken]) {
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
@@ -1037,7 +1051,7 @@
 			if (charactes.length > 0) {
 				[self reconstructActiveFormattingElements];
 				[self insertCharacters:charactes];
-				if (![charactes containsHTMLWhitespace]) {
+				if (!charactes.isHTMLWhitespaceString) {
 					_framesetOkFlag = NO;
 				}
 			}
@@ -1740,11 +1754,12 @@
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
 		{
-			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenByRetainingLeadingWhitespace];
+			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenBySplitingLeadingWhiteSpace];
 			if (leadingWhiteSpace) {
 				[self insertCharacters:leadingWhiteSpace.characters];
 			}
-			if ([token.asCharacterToken isWhitespaceToken]) {
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
@@ -2110,11 +2125,12 @@
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
 		{
-			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenByRetainingLeadingWhitespace];
+			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenBySplitingLeadingWhiteSpace];
 			if (leadingWhiteSpace) {
 				[self insertCharacters:leadingWhiteSpace.characters];
 			}
-			if ([token.asCharacterToken isWhitespaceToken]) {
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
@@ -2158,14 +2174,19 @@
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
 		{
-			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenByRetainingLeadingWhitespace];
-			if (leadingWhiteSpace) {
-				[self insertCharacters:leadingWhiteSpace.characters];
-			}
-			if ([token.asCharacterToken isWhitespaceToken]) {
-				return;
-			}
-			break;
+			NSString *characters = token.asCharacterToken.characters;
+
+			[characters enumerateSubstringsInRange:NSMakeRange(0, characters.length)
+										   options:NSStringEnumerationByComposedCharacterSequences
+										usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
+											if (substring.isHTMLWhitespaceString) {
+												[self insertCharacters:substring];
+											} else {
+												[self emitParseError:@"Unexpected Character (%@) in <frameset>", substring];
+											}
+										}];
+
+			return;
 		}
 		case HTMLTokenTypeComment:
 			[self insertComment:token.asCommentToken];
@@ -2221,14 +2242,19 @@
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
 		{
-			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenByRetainingLeadingWhitespace];
-			if (leadingWhiteSpace) {
-				[self insertCharacters:leadingWhiteSpace.characters];
-			}
-			if ([token.asCharacterToken isWhitespaceToken]) {
-				return;
-			}
-			break;
+			NSString *characters = token.asCharacterToken.characters;
+
+			[characters enumerateSubstringsInRange:NSMakeRange(0, characters.length)
+										   options:NSStringEnumerationByComposedCharacterSequences
+										usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
+											if (substring.isHTMLWhitespaceString) {
+												[self insertCharacters:substring];
+											} else {
+												[self emitParseError:@"Unexpected Character (%@) after <frameset>", substring];
+											}
+										}];
+
+			return;
 		}
 		case HTMLTokenTypeComment:
 			[self insertComment:token.asCommentToken];
@@ -2269,11 +2295,12 @@
 			return;
 		case HTMLTokenTypeCharacter:
 		{
-			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenByRetainingLeadingWhitespace];
+			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenBySplitingLeadingWhiteSpace];
 			if (leadingWhiteSpace) {
-				[self HTMLInsertionModeInBody:token];
+				[self insertCharacters:leadingWhiteSpace.characters];
 			}
-			if ([token.asCharacterToken isWhitespaceToken]) {
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
@@ -2306,11 +2333,12 @@
 			return;
 		case HTMLTokenTypeCharacter:
 		{
-			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenByRetainingLeadingWhitespace];
+			HTMLCharacterToken *leadingWhiteSpace = [token.asCharacterToken tokenBySplitingLeadingWhiteSpace];
 			if (leadingWhiteSpace) {
-				[self HTMLInsertionModeInBody:token];
+				[self insertCharacters:leadingWhiteSpace.characters];
 			}
-			if ([token.asCharacterToken isWhitespaceToken]) {
+
+			if (token.asCharacterToken.isEmpty) {
 				return;
 			}
 			break;
@@ -2342,22 +2370,23 @@
 	switch (token.type) {
 		case HTMLTokenTypeCharacter:
 		{
-			NSMutableString *charactes = [token.asCharacterToken.characters mutableCopy];
-			NSUInteger nullCount = [charactes replaceOccurrencesOfString:@"\0"
-															  withString:@"\uFFFD"
-																 options:NSLiteralSearch
-																   range:NSMakeRange(0, charactes.length)];
+			NSMutableString *characters = [token.asCharacterToken.characters mutableCopy];
+			[characters replaceOccurrencesOfString:@"\0"
+										withString:@"\uFFFD"
+										   options:NSLiteralSearch
+											 range:NSMakeRange(0, characters.length)];
 
-			for (int i = 0; i < nullCount; i++) {
-				[self emitParseError:@"Unexpected Character (0x0000) in foreign content"];
-			}
+			[characters enumerateSubstringsInRange:NSMakeRange(0, characters.length)
+										   options:NSStringEnumerationByComposedCharacterSequences
+										usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
+											if ([substring isEqualToString:@"\uFFFD"]) {
+												[self emitParseError:@"Unexpected Character (0x0000) in foreign content"];
+											} else if (!substring.isHTMLWhitespaceString) {
+												_framesetOkFlag = NO;
+											}
+											[self insertCharacters:substring];
+										}];
 
-			if (charactes.length > 0) {
-				[self insertCharacters:charactes];
-				if (charactes.length > nullCount && ![charactes containsHTMLWhitespace]) {
-					_framesetOkFlag = NO;
-				}
-			}
 			return;
 		}
 		case HTMLTokenTypeComment:
diff --git a/HTMLKit/NSString+HTMLKit.h b/HTMLKit/NSString+HTMLKit.h
index 5f2e9fd..53f963a 100644
--- a/HTMLKit/NSString+HTMLKit.h
+++ b/HTMLKit/NSString+HTMLKit.h
@@ -14,7 +14,6 @@
 - (BOOL)isEqualToAny:(NSString *)first, ... NS_REQUIRES_NIL_TERMINATION;
 - (BOOL)hasPrefixIgnoringCase:(NSString *)aString;
 - (BOOL)isHTMLWhitespaceString;
-- (BOOL)containsHTMLWhitespace;
 - (NSUInteger)leadingWhitespaceLength;
 
 @end
diff --git a/HTMLKit/NSString+HTMLKit.m b/HTMLKit/NSString+HTMLKit.m
index fe4d8b7..04870d2 100644
--- a/HTMLKit/NSString+HTMLKit.m
+++ b/HTMLKit/NSString+HTMLKit.m
@@ -8,7 +8,7 @@
 
 #import "NSString+HTMLKit.h"
 
-NS_INLINE BOOL isHtmlWhitespaceChar(char c)
+NS_INLINE BOOL isHtmlWhitespaceChar(unichar c)
 {
 	return c == ' ' || c == '\t' || c == '\n' || c == '\f' || c == '\r';
 }
@@ -42,21 +42,19 @@ NS_INLINE BOOL isHtmlWhitespaceChar(char c)
 
 - (BOOL)isHTMLWhitespaceString
 {
-	NSCharacterSet *set = [[NSCharacterSet characterSetWithCharactersInString:@" \t\n\f\r"] invertedSet];
-	return [self rangeOfCharacterFromSet:set].location == NSNotFound;
-}
-
-- (BOOL)containsHTMLWhitespace
-{
-	NSCharacterSet *set = [NSCharacterSet characterSetWithCharactersInString:@" \t\n\f\r"];
-	return [self rangeOfCharacterFromSet:set].location != NSNotFound;
+	return self.leadingWhitespaceLength == self.length;
 }
 
 - (NSUInteger)leadingWhitespaceLength
 {
-	const char *str = self.UTF8String;
 	size_t idx = 0;
-	while (isHtmlWhitespaceChar(*str)) { str++; idx++; }
+	NSUInteger length = self.length;
+	while (idx < length) {
+		if (!isHtmlWhitespaceChar([self characterAtIndex:idx])) {
+			return idx;
+		}
+		idx++;
+	}
 	return idx;
 }