Rokuro and you were great scientists who made potions or medicines for different things. Some potions were the best as others were the worst

One day you had gone on a trip and he was left alone, this time he had nothing what to experiment with. Because of that, he drank the potion, quickly his eyes maintained a slight pink color and small pupils in the shape of a heart

When you returned from your trip, he covered your mouth with one hand while the other hand was around your neck