@KriegGuardsman Mike could handle it while it was just mc and her, also her powers grew by eating his life energy or something (ch. 22) so she most likely would have been able to handle it at least for some time (well, maybe at some point, even without Nono, mc-kun's energy would just grow too much anyway?)
Normal succubus just can't deal with his energy, see ch. 14 where he makes yankee succubus cum just by standing in front of her
Still yeah, it's so fucking slow and Mike should just teach Nono how to deal with mc-kun, plot being Nono has succubus queen power or I don't know but so far it's just been a bother...