Cain tried to turn Selena on her side but he failed, the strength she was clenching her legs around his waist was no joke. His only option was to keep going until she let go.
As he was going on it, he felt Marina rest her chest on his back and lick his ear, "Cain do me as well?" She whispered. This was the purpose of all of this, after all, being able to do more than one of them at a time.
Cain knew that she didn't have the endurance or the resilience of Gracie or Selena, he can't go all out as he does with them. The best he could do was give her a single tentacle to work with and increase as the need arise.
As she was rubbing her chest on his back, she felt something creep up her leg. It was one of Cain's tentacles slowly approaching the gap between her legs.