If the events are the same, then like... a few chapters into the story. It's not like they're easy girls, but you don't have to be a genius to realize their number one goal in life is to get into the protagonist's pants. So the best way to handle that organically is to sweet-talk them. Make it clear you're interested, but don't fall for it like a desperate bastard who's never seen a tit in his life.
Both extremes are horrible, the ignorant guy who is incapable of having sex for some stupid reason and also the horny jerk who really seems incapable of thinking with anything other than his dick.
Depends on the setting but I guess not long. I don't think you would even have to seduce in most of them, you could literally do nothing and still get laid as long as you don't literally run away from the girls like the MCs do in some of those settings.
It's simple as, you just show your dick for the hand job and then enter and exit their bedroom 50 or sixty times until you're piledriving them into the floor.
I hate the oblivious harem protag trope... those MCs suck ass.
Put those retards in a harem game they get pussy... put them in an NTR game they get cucked.
It's the wet blanket retard that just serves the plot with zero personality.
It's shit devs with shit writing skills making shit games that use that kind of MC.
If it's a game like Proud Father or Unnatural Instinct . Probably a lot faster than the MC in most games . I don't think I would get far in most non-vn harems. I don't have the patience to not fuck it up.