The site does not have specific tag for 
netorase. However, my general understanding (based on how some groups on this site used it) for this term to mean wife sharing with consent, basically MC is sharing his wife, partner of girlfriend perhaps with other men willingly because usually it is his kinks (he gets off knowing or watching his wife/partner fucks with other).
This is different than the other kind of 'sharing' where MC pimps out his wife/partner for prostitution if I am not mistaken. Another form of 'sharing' is swinging, basically swapping wife/partner. But yeah, personally I don't really care much about tags because to me all of it falls into just one category "adult contents", but they are huge deals for most.
All that being said, I don't think 
netorase applies to this game. Most likely 
netori (stealing) like 
bjhbjh1234 said is the right term. But 
cheating (which is avoidable/player choice) does with the case with 
Serena. The jarl of 
Esyl himself cheats on his wife with the prostitutes and possibly 
Jamie too. Cheers.