This is... what Foster hates the most, interacting with others. The single most loathsome moment, the absolute worst. The confrontation, that accusatory feeling of someone demanding he demonstrate empathy: obligatory. And he doesn't feel anything.

He just stares at Gongenzaka--on principle now, he is defiant of this pressure.

"So? I'm a disgusting, terrible person who is incapable of caring about others! Even if they die, it doesn't affect me, so my opinion doesn't really matter, does it?"

He doesn't have hair to run his webbed claws back into, or even a mane that could serve a similar purpose. All he can do is lash his tail agitatedly, raising his talons in some futile gesture of--

Well, it's futile, so who cares what it was?