Before meeting my girlfriend I was already experienced in the open sex world, however she was not. Anyhow I soon realized how good and dirty she was in bed. From the very first moment I knew she could give steps towards a more open relationship, but guess what? she needed a little push. So I prepared this special gift on her birthday.
To respond your questions:
1.- No, he was not bigger than me (neither his cock), but more fit.
2.- No she did not cum harder. The first time she was still a bit shy, probably intimidated by the situation (at the time probably out of what her mental frame considered to be "normal")
3. The first guy did, and she said that was the best part. She moaned and grabbed his head against her puss.
4. No, but it was him (the first time) the one who fucked her, she was letting him do. The second ocassion she was playing a more active role, telling the guy (and me) what to do. I really enjoyed seeing her taking control. I remember that I was pushing from behind and the guy stared at me in a strange way, like asking for permission. Just a bit later my brave girl was swallowing his cum.