In which the MC enrolls in a special class where all the other students are potential brides to him. Rings a bell to anyone?

is it Yomekura by any chance?

Iinazuke Kyoutei is kinda similar to that (just the multiple wannabe fiancee's in the same class though), though I don't think that's really the one you're talking about.......at least I don't remember a "special class" nor was it all the other students >_<

Oh well, it sprang to mind as being similar so I thought I'd at least mention it, good luck 🙂