Val x Love Vol. 8 (manga)

Little Kururi-chan's all grown up!!
After little Kururi put on a magic helmet, she grew in all the right ways-except one. Her sweet, adorable kid-sister charm is gone-and what remains is a rebellious teenager with no interest in boys. Now, if Takuma wants to catch Kururi's attention, he'll have to pull out all the stops to help Kururi gain enough experience points to level up. But how does someone as shy as Takuma sweep a teenage girl off her feet...?!