A special deal

With a sudden crash, the man tosses the vase into the middle of the pentagram. The glow instantly grows in brightness so the room is washed in the crimson light, the same color as whatever it is was used to draw the pentagram. You hear many gasps as an odd mist begins to appear over the pentagram. Mika tries to hide behind you as Crystal seems to realize something is wrong, and her awe turns into fear.

Fear also floods your body, as you see the mist begin to take on a humanoid shape. It keeps growing thicker until it forms into an actual being. It is coal black, with fiery red eyes. And perhaps what draws attention more, it has a massive dick, which is currently limp. You feel a **** desire to run away, but some sort of trance keeps you in place, looking at it. Mika keeps whimpering behind you, probably under the same effect. You guess from all that's been going on that this is a demon. What the man is doing summoning it is anyone's guess, and frankly, you don't care, wanting only to get out of there.

"This is the secret. This isn't a farm. I have a deal with this demon, called Zer'ath. Any questions?", he explains, and you feel worry growing in your gut. A deal with a demon can't be any good. The demon has so far stayed perfectly quiet and still, his gaze staring off into the distance.

"W-what is the d-deal?", you hear a terrified voice ask. You can tell its Crystal, no longer enthusiastic about what was happening. The man gives off a short laugh.

"Now, now, we have an impatient one. Fine, I'll tell you. Zer'ath is a sex demon. The nature of our deal is that he uses his magical powers to supply me with gold as long as I supply him with a constant stream of tight pussy. That's where you visitors come in. I must say, high school has some sexy ladies, and he very much enjoys them", he explains as the true scope of the situation dawns on you. You are going to get fucked by the demon. A quick glance shows his dick is half-erect, and already is absolutely massive.

"I demand you let us go right now, or I'll tell the police!", you hear Mayumi-Sensei scream in anger. She is rather protective of you. The man laughs at her threat.

"The police, dear? What are the police going to do when a woman shows up and tells them a story about getting fucked by a demon. Not that you'll even remember. Zer'ath will make sure you remember nothing about the experience, and that your bodies are in the same state as they were when they came in. Now, boys, go outside and take a nap", he explains before commanding the boys. Your male classmates unwillingly follow his order, going out of the door, which now opens effortlessly. You however, are unable to move and make a break for it.

When they are all out the door shuts again. You now have some freedom of movement, but guess any attempt to attack the man will swiftly lead to you being frozen again. You look at Mika. The poor girl looks terrified, trembling in place. Temporarily ignoring the situation, you go up to her a give her a good hug. This seems to help calm her down.

"Now the boys are gone, the fun can begin. First off, some of you girls are a bit lacking. Let's give them a bit of an upgrade, shall we, Zer'ath?", the man says,. You don't know what is going on until you feel two orbs pressing against your own large breasts. Stepping back, you and Mika watch in amazement as her breasts grow to massive proportions, even bigger than yours, stretching the fabric of her clothing in a way that their shape is clearly revealed. Despite the bleak situation, you can't help yourself.

"Well, look who's Ushi-Chan now ", you tell her while laughing uncontrollably. Mika blushes as she realizes just how big they are now. She also seems to be having trouble dealing with the additional weight on her chest. However, her turn to laugh soon comes when your already large breasts also grow even bigger. Looking around you notice that all the girl's breasts have grown. Even Mayumi-Sensei now has a massive set of breasts, which have actually ripped through her conservative clothing, leaving them covered only by a much overstretched bra that looks like it will give away any minute now. Crystal's have also grown, and she is apparently feeling her newly expanded breasts out.

"Well, that was fun as always, but it’s time to begin", the man says as the demon steps forward. It’s time for one of you to be fucked. The demon’s dick is now nearly fully erect, and it is absolutely massive.