I'm looking for a story. I believe it was a Manga and a Light Novel.

Pretty sure it's an Isekai Revenge story with students.

Students are brought into another world.

MC is labeled as fat and useless. MC is made to fight wolves for the main group to get away.

He gets killed and eaten, is revived, killed and eaten again, and again, till he is skinny and the wolves are full.

Has the ability to resurrect other dead people as slaves.

Suterareta Yuusha no Eiyuutan (Novel) maybe ?

I do believe you're right.

Though it also seems quite dead. That's a shame.