Because Kyon is a faggot:
“Did anything worrisome happen to Michiru-chan? If you’re really that worried, why don’t you stay here for the night? I’ll be sleeping beside you too! Wouldn’t you like that ~nyoro?”
Tsuruya-san said this without looking the slightest bit nervous. She was like Cinderella asking her fairy godmother for a dress; asking me at my moment of weakness. Such simple traps won’t work on me, Tsuruya-san, and it seemed that Tsuruya-san understood that too. There was no way she would have said something like that otherwise.
I’m sure Tsuruya-san understood what I meant. Even if I agreed, I’m sure that being sandwiched in between two ravishing upperclassmen would probably derive me of all sleep. I’m tired enough, thank you. I don’t want another sleepless night.