Is it normal that i hooked up with..

my brother's wife's brother? We've been pretty good friends since high school and he's only made a move once. He tried to kiss me one night when we were really drunk but I was a little freaked out by it so i turned him down. The other night he invited me to his house (just me and him) and we drank a lot and i mean a lot of beer. We ended up in his bedroom looking at pictures and eventually we had sex. Good sex. Earlier, before i came over, we planned for me to sleep in the spare bedroom but in the morning i woke up naked beside him in his bed. it wasn't awkward at all in the morning and he actually invited me over to drink again in a few days. i'm just curious to see if people think it's normal that i hooked up with my older brother's wife's younger brother.