reverse ntr isn't netori, it's when male mc is in a relationship and get seduced ... reverse technical term doesn't mean it's the opposite, take reverse harem it's not someone being dumped by many people, it's a woman with a harem >< (just joking around because i thought your explanation was somewhat funny and not entirely correct)
though around here you should use the tag to make an explanation like that you can fuck up any reader brain : netori is cheating, netorare is netorare and cheating, netorase is swinging and cheating (even if it's definitionaly not ^^) and a couple that does not include the mc is cheating and ntr even if it's the parent of the mc (probably some ntr enjoyer propaganda to brainwash people into thinking we are all the result of an ntr relationship ><)
and that just for the "cheating" if you look a bit, half the tag are used in a misleading way ... everytime i look up a game i feel like i'm opening a "virgin blond teen get blacked" porno with a rusian dude droping black paint on an asian girl with a pussy that look like a purple cabage ...
What's been piled up here will only confuse things further.
-Netori is cheating, and that's the only correct explanation.
-Netorare or NTR is when the protagonist's beloved is seduced and taken away.
-Netorase or NTS is when the man is aware of his woman's infidelities and approves of or facilitates them. (The closest European term is hotwife or sharing).
To make things even easier to understand,
if a woman cheats without her man's permission or knowledge, it's technically netori; if she subsequently leaves him, it's NTR.
All other cases are NTS, except for swinging (there's no name for this perversion in Japanese culture).