They orgasm!

You shove two fingers into Ice and Fire's tight and exposed assholes at the same time! The result is...orgasmic.

"Oh shit- gonna cum," Ice says.
"Me too! Cum with me-ee," Fire replies.

The Superheroine duo press their faces into each other's pussies as your backdoor stimulation pushes them over the edge. They cum in unison- thankfully with the sound muffled by their own bodies.

You're pretty sure that they would have been loud enough to wake the dead...which is a concern when Deadman and Swamp Thing are both in the Justice League right now.

When the orgasm passes, both woman breathe heavily and pant a little. They're in tip-top condition, otherwise an orgasm that massive would have really drained them. Ice rolls off of Fire and lays there, reacting to what just transpired.

"I see our little plan worked," Ice says.
"Yeah. I knew he'd do you after I planted the seeds, but doing me," Fire says, "Bonus."
"You'll be happy to know that a Doctor with an Advanced Degree and a technologically-enhanced brain can take a hint sometimes," you reply with a smile.

The two Ladies laugh at your joke, still recovering from the exertion.

"There's only one problem now," Ice says.
"You kind of spoiled the contest," Fire adds, "We came together that time."
"On the contrary," you say, "I think it worked out just fine. You ladies ready to go again?"

The pair nod, awaiting your suggestion/command.

You tell Ice to stay where she is, back-first on the bed. You move Fire over towards her, getting her to lay on top of her friend.

Now the fun can begin...