>>32362922There's a Japanese horror comedy short called Guinea Pig: He Never Dies about an immortal salaryman who cuts himself to pieces. He's not shown to be in extreme pain but there's a lot of practical gore effects that I find satisfying to watch.
For something that's less gratuitous and just disturbing check out the 1973 b&w film Johnny Got his Gun.
For horror/disturbing movies that involve men being tortured with women, check out Salo and
A Serbian Film.
Btw the latter isn't well written it's mostly shock. This is less related to what you want but for pure kino please watch Funny Games(2007/1997) about two parents and their son getting psychologically abused and killed by a pair of psychos in the most intentionally-frustrating and ungratifying way possible.
