The rest of the day passes awkwardly. You can barely focus on anything but your fantasies about Mina. When the bell goes at the end of your last lesson, you're relieved to go home, and while you ride the bus you idly read some smut on your phone to ease the tension. Just to underline how your gender and sexuality have changed, you realize you're subconsciously focusing more on the descriptions of the men, their cocks and their firm bodies than of the women, their pussies and their tits.
Once you get home, you race to the bathroom, not wanting to have to explain what happened to your parents, particularly with what your mind is focused on right now. (Thankfully, the school sent out an email explaining things, so they know.)
Pulling off Mina's clothes, you hop into the shower, and turn it on to a warm but gentle setting. You've heard vaguely that girls like to masturbate in the shower, so you figure it should be interesting to try. Once the water's heated up, you detach the shower head and aim it over your softer skin. Your breathing deepens- it's weirdly exhilarating. At first, you can't aim it and are clumsily spraying your stomach, but then you move to your boobs, and water channels down them as your nipples grow hard. You cup your soft flesh eagerly, and feel a warm shiver pass through you. More of them come when you start rubbing your nipples. It's weird to think how as a boy these barely did anything, but as a girl they're one of the most sensitive parts of you.
Lowering the shower head, you spread your legs and spray the water against your crotch. You bite your lip to keep from moaning. It's hard to explain how, but feeling the flood rubbing along your passage and your clit feels like magic. You lean against the wall as you thrust your hips against it, and after continuing this motion for a few minutes, a little yelp-like moan escapes your mouth as you cum. Your legs shake and you almost collapse from the pleasure.
To your surprise, though, you don't feel totally spent like you would after orgasming as a boy. Your horny feelings surge back up quickly, as images of Mina's handsome body mounting you fill your head. Even if they seem less horny than boys, apparently girls have much more staying power with sex.
As if your sexual fantasies weren't oddly specific enough, suddenly you realize those kinds of thoughts are getting you going- remembering that you used to be a boy and have been turned into a girl. Wanting to continue to indulge yourself, you hide your nakedness in a dressing gown, sneak to your bedroom, lock your door, throw off the dressing gown and lie on your bed. Looking down at your body, you start to rub yourself remembering your and Mina's changes. You paw at your boobs, thinking about how they swelled up and became much more receptive to pleasure, pinching your nipples as you imagine Mina sucking and teething them. Soon you're imagining him grinding his cock between them, and fapping it until he shoots his seed onto your tits.
His seed... he can fill you with his seed. You remember feeling your crotch flatten and a vaginal passage forming inside you to be fucked, your fingers slowly thrusting in and out of where your body was recently opened to take things inside you, recalling Mina's balls slapping against your body as he pounded you. Your thumb rubs your clit, your former cock which shrank while Mina's swelled into the cock that filled you, that's going to fill you again.
As you hit your peak, everything seemed to go blank for a moment, and you could focus on only one fact: this was how good it could feel to be female.
Slowly the real world irised back in on you, and looking at your hand that had just come out of you you saw a surprising amount of wetness on it. Nonchalantly, you grab a tissue from the box next to your bed and clean your hand and slit. Masturbating is messy regardless of gender, you realize.
While you get dressed again, a name dawns on you that you like the sound of. Picking up your phone, you text Mina, 'I've decided, my name is...'