Capítulo 787: Innocent Mimi, Meeting

Actually, Avelia was telling ecchi stuff to Lily, like how they will do that and do this tonight with Athan and disappear all of his exhaustion and pent-up desire that was stored for decades.

They didn't want to tell Mimi about that stuff because if they said it, they felt that that would occupy her mind, and her target of affection would probably become Athan. 

It was not like they were against it, but they knew that Athan would never be able to see Mimi as such since he had always treated her as his sister. So until Mimi finds someone else attractive and falls in love with someone, it is better to keep her in the dark about it.

...

After everyone knew the details about Grand Meet, Lily asked with a frown, "so...Athan, you and Avelia are going to participate in it?"

Her fists were clenched in frustration again because...She was not strong enough!