diff --git a/class.go b/class.go
index f629be3..8cd9be5 100644
--- a/class.go
+++ b/class.go
@@ -12,6 +12,14 @@ var methods = map[string]*Method{
 	},
 }
 
+type RClass struct {
+}
+
+func (mrb *State) ClassOf(v Value) *RClass {
+	// NOTE: Null Pointer fallback to FalseClass
+	return mrb.falseClass
+}
+
 func (mrb *State) FindMethod(recv Value, mid string) *Method {
 	if m, ok := methods[mid]; ok {
 		return m
diff --git a/irep.go b/irep.go
index 1ed0aa3..204bf19 100644
--- a/irep.go
+++ b/irep.go
@@ -84,10 +84,14 @@ func (ir *iRep) Execute(state *State) (Value, error) {
 			b := ir.iSeq.ReadB()
 			c := ir.iSeq.ReadB()
 
-			ci := state.PushCallinfo(ir.syms[b], c)
+			regs[a] = regs[0]
+			opCode = opSend
+
+			ci := state.PushCallinfo(ir.syms[b], c, nil)
 			ci.stack = append(ci.stack, regs[int(a)+1:int(a)+ci.numArgs+1]...)
 
 			recv := regs[0]
+			ci.targetClass = state.ClassOf(recv)
 			method := state.FindMethod(recv, ci.methodId)
 
 			if method == nil {
diff --git a/mruby.go b/mruby.go
index ebafd49..865d62c 100644
--- a/mruby.go
+++ b/mruby.go
@@ -12,9 +12,10 @@ type Method struct {
 }
 
 type callinfo struct {
-	numArgs  int
-	methodId Symbol
-	stack    []Value
+	numArgs     int
+	methodId    Symbol
+	stack       []Value
+	targetClass *RClass
 }
 
 type context struct {
@@ -28,6 +29,8 @@ func (ctx *context) GetCallinfo() *callinfo {
 
 type State struct {
 	context *context
+
+	falseClass *RClass
 }
 
 func New() *State {
@@ -36,6 +39,7 @@ func New() *State {
 			ciCursor:  -1,
 			callinfos: []*callinfo{},
 		},
+		falseClass: &RClass{},
 	}
 }
 
diff --git a/vm.go b/vm.go
index 644b947..fc9f55f 100644
--- a/vm.go
+++ b/vm.go
@@ -1,12 +1,13 @@
 package mruby
 
-func (state *State) PushCallinfo(mid string, argc byte) *callinfo {
+func (state *State) PushCallinfo(mid string, argc byte, targetClass *RClass) *callinfo {
 	ctx := state.context
 
 	callinfo := &callinfo{
-		methodId: mid,
-		numArgs:  int(argc & 0xf),
-		stack:    []Value{nil},
+		methodId:    mid,
+		numArgs:     int(argc & 0xf),
+		stack:       []Value{nil},
+		targetClass: targetClass,
 	}
 
 	ctx.ciCursor++