I think my brother is acting really weird what should I do?

I dont even know how to say this but I'm just gonna say it as it is ( NSFW WARNING )

my older brother and I are bestfriends but he does something that he's done for alot of years and nobody else says anything , he will literally play with his dick under his pants whenever we are in the living room and it makes me so uncomfortable and grossed out, he also has been doing more weird things too like rubbing his feet on me as a "joke" and just saying really weird shit and it makes me so uncomfortable, and I'm sorry but he also stinks really bad and i never wanna be around him anymore because of all of this . and idk what to do, or if I'm just overlooking it but it's getting more and more weird. I love him and I just wanna be able to be around him again but it's genuinely disturbing