The anime is a lot more servicey, adding in more almost lip touch moments than the manga ever had. In the manga there's a few jokes about characters being attracted to Tsuzuki and resisting it, and certainly the prettiest eyelashes and most shapely bums happen whenever the guys get close to one another. I've seen old fansites refer to it as BLppoi, or BL-ish, as a sort of aesthetic to please readers without actually going anywhere. I guess that means it's for the sake of eyecandy.
But yeah, pretty much. All the active homosexuals in St Michaels get killed off horribly and it's implied a demon drove them to act on their desires to begin with (Mitani-sensei is treated really kindly for a while though). I've seen Japanese fans say Matsushita had some angry outburst about how she's never done BL and none of her characters are gay, but the only evidence I can find is her complaining she's never done doujinshi so please stop asking. I think she's ashamed of the homoerotic moments she did before, the redraws try to switch out some surprise naked Nagare for more art of his wives, Kasane and Rui.
She likes pretty men but she's not entirely committed to what she wants them doing. Every character comes with a no homo excuse but puts their arms around another while making bedroom eyes. They only briefly get to do the same with the opposite sex, and sometimes that opposite sex is Tsuzuki with tits.