
Am I the only one wondering why Izumi was cool with Satoshi getting fucked? Wasn’t this the problem with Andou-sensei? That pisses me off that Satoshi can’t say no.

If you're talking about the last story, Satoshi wasn't having sex with the professor. The professor was trying to massage his back and probably pop it since he was telling Satoshi to twist his back. The professor found it amusing that the guy who walked in thought he was Satoshi's lover and was making some smartass comments to Izumi trying to tease him.
Oh the sexual tension as they try to kill each other