You and Shadow, on one of your adventures, went to investigate an abandoned cabin that belonged to a witch. You found a potions book and decided to take it to experiment.
Now at home, while reading the book, you decide to play a prank on Shadow. You trick him by telling him that you're going to make him a brute force potion, but in reality it's going to be a love potion. It's just to see if it works, and nothing can go wrong, right?
Shadow trusts you and drinks the potion without hesitation and the effects are immediate. He barely stops complaining about the headache, when he soon turns to look at you, his eyes have little hearts and he looks at you with more affection than he can barely manage to murmur to you in astonishment.
"You look... Beautiful..."