It's an omegaverse (tragic or bitter-sweet depending on the reader). There are 2 brothers (I think they were twins), one alpha the other omega. The alpha brother is secretly in love with his best friend who is also an alpha. One day after school the alpha best friend forgot something he left behind and ran back to the classroom, where the omega brother was in heat, and the alpha best friend went into rut and claimed the omega brother which resulted in a pregnancy. The parents found out and the omega brother was taken out of school, while the alpha's parents pleaded for him to finish school in order to better support his now new family. Some time passes where the omega brother dies and has left behind a letter for his alpha brother, confessing that he knew his brother's love for the alpha best friend whom he stop seeing, stating that he was jealous of their relationship and that's why when his heat came he took advantage of the situation and stole the love of his life away, because he wanted to have something for himself that his brother loves with all his heart. At the end the alpha brother and the alpha best friend reunite (along with the child he had with the omega brother) and the child looked at the alpha brother as if he was their omega mother because they look so much alike. I only read this once and wish to read it again.

AnGELs N DeMONs

Chapters 1-3 of Hebi no Seikatsu?

Thank You So Very Much!!! 😃

AnGELs N DeMONs