diff --git a/item.go b/item.go
index e191f46..27c5c76 100644
--- a/item.go
+++ b/item.go
@@ -58,6 +58,11 @@ func (b *Item[T]) Trans() (tb *Item[T]) {
 	return tb
 }
 
+// HasInvolved whether this item is buffered.
+func (b *Item[T]) HasInvolved() bool {
+	return b.stat.isbuffered()
+}
+
 // IsTrans whether this item has been marked as trans.
 func (b *Item[T]) IsTrans() bool {
 	return b.stat.isintrans()
diff --git a/pbuf/bytes.go b/pbuf/bytes.go
index 17235ab..3f07b07 100644
--- a/pbuf/bytes.go
+++ b/pbuf/bytes.go
@@ -87,7 +87,10 @@ func (b Bytes) Copy() (cb Bytes) {
 // SliceFrom dat[from:] with Ref.
 func (b Bytes) SliceFrom(from int) Bytes {
 	if b.buf.IsTrans() {
-		return InvolveBytes(b.dat[from:]...)
+		if b.buf.HasInvolved() {
+			return InvolveBytes(b.dat[from:]...)
+		}
+		return ParseBytes(b.dat[from:]...)
 	}
 	nb := b.Ref()
 	skip(nb.buf.Pointer(), from)
@@ -98,7 +101,10 @@ func (b Bytes) SliceFrom(from int) Bytes {
 // SliceTo dat[:to] with Ref.
 func (b Bytes) SliceTo(to int) Bytes {
 	if b.buf.IsTrans() {
-		return InvolveBytes(b.dat[:to]...)
+		if b.buf.HasInvolved() {
+			return InvolveBytes(b.dat[:to]...)
+		}
+		return ParseBytes(b.dat[:to]...)
 	}
 	nb := b.Ref()
 	nb.buf.Pointer().Truncate(to)
@@ -109,7 +115,10 @@ func (b Bytes) SliceTo(to int) Bytes {
 // Slice dat[from:to] with Ref.
 func (b Bytes) Slice(from, to int) Bytes {
 	if b.buf.IsTrans() {
-		return InvolveBytes(b.dat[from:to]...)
+		if b.buf.HasInvolved() {
+			return InvolveBytes(b.dat[from:to]...)
+		}
+		return ParseBytes(b.dat[from:to]...)
 	}
 	nb := b.Ref()
 	buf := nb.buf.Pointer()