After visiting her enough times, she will have sex with you and your slave. If your slave's Obedience is too low, this event will be refused, but can be attempted again later. Your slave will gain +0.5 Sensibility / +0.5 Constitution / +1 Fucking / +1 Nymphomania / +1 Tiredness and -0.5 Lust each time she has sex. If she's being trained as a Lesbian Slave, she will gain +0.5 Sensibility / +0.5 Constitution / +1 Trib/Strap-on / +1 Cunnilingus / +1 Nymphomania / +1 Tiredness and -0.5 Lust instead.
You can attend a party with Miss N as many times as you want. To start the cycle of parties, you need to wait until after she starts offering sex. Regardless of whether your slave refuses the sex or not, you can Visit her while Naked to hear about the first party. She will say that it is in 3-4 days.
If you choose to attend the party, she will pick up your slave at night, so you cannot do any Night Actions that day. During the party, you can do one of several things that will boost a large number of your Statistics
After the party, Miss N will say that there is another party in 3-4 days, so you can repeat the process and attend as many parties as you wish.