AthalosJ, I get the feeling that was intentional. Either by the translators (as a troll, uh, er... Joke) or by the actual mangaka, probably for the same reason...
But, it does fit. Not to say he is homosexual or bisexual, but as a simple one-time reaction to what happened. Shock/surprise can make people say/think things or think things 'in ways' that they wouldn't otherwise.
Oh, also, he did just literally get out of a hot springs equivalent bath... So he likely was 'literally' "hot"...