Pocket Monsters: PiPiPi★Adventure

When young Hazel develops a crush on Almond, a Pokémon trainer, she goes to her Grandpa, an inept magician and Pokémon researcher, for a love potion to hook him. But the resulting potion doesn't make hearts flutter—it makes Grandpa's lab explode, because he doesn't have much practice with potions. For the promise of more and better love potion, Hazel is convinced to travel the world studying any Pokémon she finds... but always chasing Almond!

(Source: Viz Media)