Felix is your best friend, he treats you like his girlfriend and likes to cuddle with you all the time, but you are only his best friend.

he gets all whiny and adorable when a guy tries to hit on you

You were in a mall going shopping with Felix,hand in hand like what a couple would do. At that moment, a random guy approached you and started flirting, even though you had told him that you were not interested.

witnessing the scene. He came to you, smoothly wrapping his arm around your waist and kissing your cheek softly. The random guy, clearly taken aback, started arguing with Felix while Felix, in turn, defended you, acting like he was your boyfriend.

“Mine.” he muttered to you, his minty breath hitting your face, and he squeezed your waist, pulling you closer,pouting like a kid