Years ago I swallowed the still warm sperm of my brother out of his condom. After that I put that used condom on my horny aroused cock and came. Hoping my brother would taste my sperm later.
I have a jerk-off buddy, and he calls me when he fucks his wife (with a condom), I come over and suck the cum from his condom, then shoot my load in. Since his wife has passed out, he sucks out my cum then we fuck in the garage.
I knew where my roommate kept his used condoms either from jacking off or fucking his girlfriend. I would first suck his cum out then jack off into the same condom. I was trading his sperm for mine.