Comment by My name is mariaaa on Eyes clouded by the tiger - Chapter 51

Dark Heaven, is kinda sad but it ends beautifuy 
it has several trigger warning tho, such as ; r4pe, bl00d, kn1fe k1nk, d3ath, abuse, rasicm, homophobia, etc

thirst is so great

"Ookami wo Karu Housoku" technically has a switch couple, but the manga adaptation is very mild and doesn't show the switching, so you would be better off reading the novel.