So far...I got...
A magically magical academy of magic...the one from the previous description. Essentially the main is on their last year at the academy. The academy houses students from many magical races, all students in the child to adult age, lesser talents to greater talents. The main is possibly the most powerful magic user to attend the academy, and potentially the most powerful magic user in the world's future, due to having the ability to unlimitedly learn and master all elements and classes of magic...race specific magic, one of a kind magic, all of it. Of course, they became a mega snob with a superiority complex, due to this. Bullying and mistreating other students, staking a magical claim on other people's objects...it doesn't help that they were adopted into a powerful magical nobility's family, due to this potential. No student, no teacher, not even the headmaster could really raise even just a (middle) finger against them.
Of course, their luck just about ran out. Waking up one morning...they found...their magic sucks! They can't even fluff up their pillow with air magic, or clear the dirty floor with ground magic, or heat up half a cup of water with fire magic...what's going on?! Going to the headmaster to be checked for curses, and maybe look for general answers...
"Gramps, what's going on with my magic?! What curse is this, exactly?!"
The man merely chuckled, before magically hovering his wheelie chair to face the large window, "...heh heh heh...fuahahahahahahahahah~!"
"W-w-what? WHAT?!"
"This is no curse, a mere curse can be undone with strong enough counter magics! This...this is somebody's wish. From the bottom of someone's heart, they wished for this horrible person's magic to become almost nothing in power and control...!"
"Why you--! Grr...! I-isn't this basically a curse? Just fix this already!"
"Wish magic, as you must know, much of it is still unknown to humanity...and a great wish like this, it cannot be undone without the wisher's mind being changed about it. And...still...even if I could undo this...why would I?" The headmaster chuckled darkly at the desperation in the face of the once powerful and great student.
"I'm from a powerful family! My father will hear about this!"
"And what would he do...? I hear his actual blood children have much magical talents, it'd be easier to train them to magical mastery than try and undo your predicament." The man smiled, tapping his chin thoughtfully, before continuing, "Hah...alas, I will give you some aid, advice, push you in the right direction...befriend all of the possible students. Relearn what you once knew, but in a different or unorthodox style, as you still have magic running through your veins. Make pacts with the powerful magical beings and contracts with familiars, the ones you previously rejected. If you befriend everyone, you may have a chance of befriending and changing the mind of the wisher, if they aren't graduated or from outside of the academy. The djinn, fairy, and the others were quite offended by you rejecting their costless pacts...but with some groveling, one may take pity and give you a conditional pact. At this point, though...you may have to buy a familiar, as the powerful ones who've been slighted will never offer their contract a second time, unless you really work towards their affections. I wish you luck, as you only have one year...remember? You taking this last year would be a favor to this '$#!t-hole of a dump' academy, a formality...? After this year, no one would be able to drag you back in here, kicking and screaming...right?"
It was then...that the protagonist fainted. Like a b!tc#.
Waking up in their room, is when the dating sim starts...the mains wake up, and begin their first year as a magic academy where everyone hates their guts.
Let me know if I should add/remove/change anything.