Help me find this!(Yaoi)

So theres this manhwa where the mc is from the slums and his body dies wihout seeing his best friend for the last time(ML). He wakes up in the body of a rich kid(same age different height), who has a twin. Oh and the original owner of the body the mc's in is suffering depression(?) The MC originally was a fighter and save the ml when they were young(when the mc was still alive in his og body). And when the MC and ML meet, the ML feels the vibes he got from the MC was like from his bestfriend(MC who is dead to him). ML is an illegitimate child who is taken by his biological father to replace his sick son.(So the MC and ML never had any contaxt because of this). This story was already completed but I can't find it!!!!!!! ╥﹏╥
NOTE: IT HAS THE SAME AUTHOR AS "MAD DOG"