Kissing Tavros was probably a lot like kissing a very soft statue. He didn't know quite what to do, so when Karkat opened his mouth a little, creating a little friction, he didn't really do anything. Because... well. What do you do? His lips did twitch a little, but other than that, he just stayed kind of still, though he pressed into it a little more.

He squeezes Karkat's hand gently as it was guided down, and when Karkat's nose brushed his, he giggled. He didn't mean to, but it tickled a little and between that and the butterflies in his stomach, he had to laugh. The action forced his mouth open against Karkat's, and then a realization hit him. All he had to do was... stick his tongue out, and he would be doing what Karkat had done. All the motions except for that had been taken because of the laugh that had forced its way out.

The butterflies were telling him to go for it- he'd learned that when he thought of something, and they flew around, it definitely meant he wanted to. It was just listening to them that was the hard part part. They flew up his stomach, once again making him feel like he would fly away, and then all of a sudden he just... did it, and they exploded as his tongue flicked out and brushed against Karkat's bottom lip.