You're Invincible Now, Disciple. Go Find Your Senior Sisters

The Male Lead Hides in Prison, Until His Father Forces Him Out to Marry a Female War Hero

The male lead manages all the big shots in prison. After his release, everyone inside wants to curry favor with him so they can live more comfortably in prison. The heroine is the military's only female war god, but she doesn't want to accept her family's arrangements. She wants to find the male lead to break off their engagement, and it turns out he wants to do the same.