Surprise them with your powers

With a quick thought, you turn yourself into a ghost.

"C'monn... Nick, are you coming?" Luna continued to tease. She also continued to tease Ava, playfully wrestling her hands off her chest, replacing them with her own. "Because Ava here will be soon..."

As if on cue, Ava let out a slight whimper.

"See? You don't have all day, Nick!" Luna said, oblivious to the fact that you had gone invisible, and that you were mere feet in front of her.

"Nick! Your girlfriends are waiting..." Luna cooed.

"G.. girlfriends?" Ava stammered, blushing even harder as Luna fondled her boobs.

"Well yeah... we just agreed to it! You even said so!" Luna exclaimed.

"Ah... right..." Ava whispered.

You admired the sight before you. Ava and Luna, two goth goddesses. Ava and Luna, both completely naked. Ava and Luna, who had just proclaimed themselves your girlfriends. Ava and Luna, waiting for you to have your way with them... and you, a ghost, with power well beyond anything you had ever dreamed. Sure, you could simply have a threesome with the girls. As amazing as that would be, you could do so much more.

As you floated ever closer, the girls finally noticed your absence.

"Nick?" Luna called out, letting Ava's tits go as she did. Sure, Luna did objectively have the bigger (and nicer) pair. But Ava had one hell of a killer ass. An ass that you had been wearing, only a few minutes ago. And you hadn't gotten to have as much fun as you had wanted.

But now...

As Luna had said - you had already possessed Ava, and Luna wanted her turn. You could take over her and continue to play with Ava... or you could try out other powers.