Kazami believes Seiji doesn't want to admit that he liked watching her with cat ears on. Seiji's embarrassed for a completely different reason, and her offering him more service was the wrong thing to say,Seiji doesn't know anything about girls out side of two D, and he doesn't want to admit where his thoughts are going, because of what her actions would mean in the two D world wwwww.

誠司「俺がご主人様だから、首輪を付けないとな」
風見さん「にゃッ(ΦωΦ)!?」

そしてまた自爆するのでしょうか……？（笑）