Protagonist

Dan

Rosa

There's two playable Protagonists in Adventure High: Dan and Rosa (though always refered to as The Protagonist on this wiki with a handful of exceptions, such as dates that requires you to play as either Dan or Rosa).

The Protagonist is a childhood friend of Valerie, or Val for short.

The Protagonist has as of version 0.35 thirteen spells, of which one is Hidden.

Sarah is only datable if you're playing as Dan.

Rosa currently has no female-exclusive relationships but will have one with Cassandra in the future.

While a normally calm person, it's up to the player to decide how the Protagonist is in the end: Either a caring person who wants to stop Drape from abusing his power to change school to his fitting, or enslave everyone in the school. Or, hell, cause everyone to turn into bimbos.

The Protagonist lacks any damaging spells initially and as such relies on his/her teammates to deal damage, or (as unlocked later) the Confuse spell to make enemies hurt themselves.

The Protagonist can naturally not use any magic and is as such considered "giftless". It's unknown as to why - or how - this happens for certain people.

There's a handful of scenes that requires the player to play as either Dan or Rosa. However, in general, this mostly just affects minor story details. With a few exceptions.

Trivia

The Protagonist starts with 100 HP.
The Protagonist is the first character able to use all four kinds of spells.
The Protagonist's family is apparently so poor they can't afford a Crystalizer to obtain Gems. Instead, s/he is given Molly's old one the first time they visit the Item Shop, as Molly "can purchase a new one".
If you choose to tag with Molly during the Bimbo World New Game +, the Protagonist won't obtain magic from the Sigil. Instead, Val has to give it to the Protagonist in secret.
If you choose to tag with Julia during the Mysterious Book New Game +, the Protagonist won't obtain magic from the Sigil. Instead, Val has to give to the Protagonist in secret. Julia, however, remarks that she was aware of his lack of magic but thought she was incorrect about it. Julia is then surprised at the fact that the Protagonist's gift - as well as Val's gift - changed.
Despite remarking that the school has no dress code, the Protagonist and Derrick both dress quite formal compared to everyone else, who - supposedly - wears clothes they find comfortable or otherwise like.
The Protagonist is most likely a year older than everyone else, as the Protagonist was one day too young to enroll in the school.
This is further evidenced by Molly's Japanese School Girl outfit, in which she refers to the Protagonist as "Senpai" (meaning "senior"). However, that could possibly just be for appeal.