how long does sperm take to dry on the inside of underwear and pants?

long story short, i ejaculate with my underwear on, sometimes goes through my pants, but i dont change, i just wipe it off with toiler paper till it seems "dry" but it still kind of wet, so i let it dry on its own. but i was just wondering how long semen takes to dry on underwear and pants (from the inside of course) because i may be overthinking this, but because we all put our underwear in the same machine (especially girls) it may be possible the semen on my underwear and pants hasnt dried fully and washes onto the girls panties, and the semen goes inside next time she wears them? its something ive been paranoid about for a while and its stupid i know, but i need to confirm.