So about Rock Lee and sadism.
Every taijutsu specialist likes punching people, it just comes with the territory. You can't be a master at hurting others physically and spend your life doing that if you dont enjoy it. I keep thinking Lee probably has some guilt about his "sadism", and thats part of the reason why he's so adamant about stopping fights during the chunin exam (we are not animals people!!) even though its extremely hypocritical of him, since he started like three fights when he wasnt supposed to.
fight against Naruto (in Lee's defense he kinda didn't want to fight Naruto at that point, but im still counting it)
fight against Sasuke, legit assault by Lee lol, this was fully unprompted Lee just wanted to kick his ass shh I know this fight is way deeper than that for both characters but its funny to explain it this way
and kick against Temari, which I count as a fight (or at least a hostile encounter?) cause Temari could've taken the bait
also about the Sasuke fight, he was literally gonna Primary Lotus him? like thats gotta be sadism! come on! It's not explicitly stated but the Primary Lotus is meant to kill, or at least that's what i gather from the way it's performed and the fact that you have to open the first gate to do it. (and if not kill, its meant seriously harm someone)
ah yes, Rock Lee, my sweet innocent boy that has violent urges he can barely control <3