[Does push the jacket off just enough then, hands continuing to press over the fabric of his shirt. It's more of a totally pleased exhale than a laugh when Shiro turns the tables a litte bit, when that second button opens up.]
Hmmm... dunno. Seems like a lost cause to me. [Presses closer if possible, very near to a smile in his expression back at him as he plays along.] You know I just can't keep my shirt up to code.