Yes/Chad/Just help her with her confidence and see what happens
The girl just lacks confidence. With added self-confidence, you're sure she would start taking more interest in her appearance, and be willing to be more open about what she does and does not want.
"Mina," you say, cautiously phrasing your sentence in your mind before you say it, "from now on you will be confident in yourself. You will know your own worth and limitations, and not be so shy and reserved. Isn't that right?"
"Yes," she says, visibly relaxing and looking you straight in the eye. "How did you do that?"
Damn . . . from now on did that . . . at least you think it did. Let's see, nerdy girl . . . magic or superpowers? . . . Harry Potter or the Avengers? Avengers. You like Tony Stark a hell of a lot more than Dumbledork. "I have superpowers."
"No," she says, "really? Like Professor Xavier?" Bingo! Super heroes it was . . . though it actually could have been both you suppose.
"More like Superman, but without any of his weaknesses and limitations . . . and with the ability to alter reality in small ways."
"No way!" she says jumping up and down a little. "Then what do I have in my back pocket?"
You use your x-ray vision to look in her pocket, but can't help but check out her body as you're at it. It's a nice body, a little soft for your preference, but not at all plump. Her breasts are quite large, but could use some extra support you imagine as they seem to be tugging her bra down more than you think would be desirable. You also notice that her hymen is intact . . . sweet, a virgin. Oh, yes . . . her pocket.
"A black and white rabbit's foot key chain," you say confidently.
"No way! That's awesome!"
"Hey," says Gwen, a bit annoyed, "I'm here too."
"Sorry," says Mina as she turns to your sister, "I didn't mean to ignore you, I'm just a huge super hero fan. Maybe this will make it up to you." She nervously pulls Gwen in, and kisses her tentatively on the lips. Gwen pulls her in, and takes the lead, kissing and fondling your new friend. The girls make out for a while, waking your cock once more. You watch for a bit as it gradually becomes steamier and steamier. Finally, feeling a little left out, you clear your throat.
They both look up at you, the passion still hot on their lips. "Oh, poor Chad," says Gwen, "do you want in on this?"
You answer her by taking them both in your arms. You kiss Gwen, then Mina, then guide them into a three-way kiss. Well, this is going swimmingly.
What's next?