There was an incel character on the show named Miroku, he was always trying to impress Sango - but like a typical foid, she thought Miroku was subhuman.
Miroku wasn't incel he was a based Chadlite who simply went around asking foids to bear his children - he was honest and far more heroic than someone like Inuyasha who kept pining for Kikyo who hated him and not admitting he wanted to fuck HS girl Kagome.
Truecels are too high-inhib to constantly grope stacies and proposition eleven-year-old girls. If they ever did they'd instalt get murdered, but when you're a Chadlite all you get is a light face-slap and they let you continue your flirtatious patterns because ultimately the girls enjoy that kind of attention when it comes from a good-looking guy who doesn't overdo it.
Sango obviously likes him and falls for him despite him constantly doing playful grab-ass to her (and others like Kagome)
basically he gets a pass on this since he's terminally ill with like a year to live because of the black hole in his hand that progresses faster than the worst cancer
that and he obviously does do things to help others which causes far more benefit to them than whatever sekuhara cope he does along the way.
If Miroku wanted to seduce a woman I'm pretty sure with his looks/personality he's capable of doing so, I believe he chooses not to and plays the womanizer as a coping mechanism because he doesn't want vulnerable and weak women to get too close to them, because ultimately he doesn't think they'd be able to cope with his inevitably death.
I think that's ultimately why he orbits Sango because she's a warrior and a strong woman and most suited to deal with the heartbreak when something happens to him. You see the same thing with guys like Bruce Wayne who flock to female badasses like Talia al Ghul or Selina Kyle who have already dealt with a lot of dark shit, and why ultimately he doesn't gain any ground with the various socialites he's dated like Selina Kyle or Veronica Vreeland.
IY basically had no reason to hide his feelings, he's a near-indestructible wolverine-like demigod and any girl he dated would never have to worry about him dying. It's the opposite - he knows Kagome will get old and he can't deal with outliving someone he loves, so he pretends to be loveless. Unlike Miroku who is protecting others from loss, IY protects himself from loss.
Well that or he really isn't confident he can take Naraku and expects to die and is waiting until that threat's passed before he impregnates humans like his dad.