Noelle Silva is a mage from the Clover Kingdom and belongs to the order of the Black Bulls. She's one of the best water mages in all the Kingdom, but the danger was increasing, so she wanted to be stronger, to fight alongside her beloved friend Asta. She drank a serum to increase mana, but things didn't turned out as expected, making ger grow into a gigantic girl eager of pleasure. After growing bigger than the capital of the kingdom (and lots of pleasuring herself) she gain consciousness again, looking what she did.
"THE CAPITAL! But most important... I'm HUGE AND NUDE?!
Fortunately she shrank back to normal, Sally's theory indicated that masturbating caused all the excess mana that was in her body to be released, and that was surely what made her grow too. Her partner Vanessa, who was nearby, managed to see the girl, and quickly with her thread magic made her some clothes, just enough to cover her body, and lent her some boots she jut bought. Noelle was still very grateful for the help and asked Vanessa not to say anything to the others.
Embarrassed, she helped rebuild the wall she'd smashed with her enormous foot. Suddenly, Noelle's body felt warm again, and much faster. She was familiar with this feeling, so she ran as fast as she could out of the capital to avoid causing more damage, until she couldn't anymore, and the serum was activated again.
Faster than the last time, it began to grow, and she couldn't resist again, she began to touch herself as the suit that Vanessa made her became tighter and tighter, which didn't last long against her growing body, her shirt ripped revealing her tits, just as her skirt became so small until it ripped revealing her butt. Her legs too, and her feet burst out of the boots he had been lent, breaking them without much effort.