Reject unescaped-multi-line-string
diff --git a/src/_decoder.pyx b/src/_decoder.pyx
index cc83b4e..03606da 100644
--- a/src/_decoder.pyx
+++ b/src/_decoder.pyx
@@ -190,13 +190,16 @@
     cdef StackHeapString[uint32_t] buf
 
     while True:
-        if c0 == delim:
+        if expect(c0 == delim, False):
             break
 
         if expect(not _reader_good(reader), False):
             _raise_unclosed(b'string', start)
 
-        if c0 != b'\\':
+        if expect(c0 != b'\\', True):
+            if expect(c0 in (0xA, 0xD), False):
+                _raise_unclosed(b'string', start)
+
             buf.push_back(c0)
             c0 = _reader_get(reader)
             continue