He kissed my jawline, how should I respond?

Anonymous
So, I've been dating this guy for 5 months, and he has started to kiss my neck when we part ways, just a fleeting peck. At first, i didn't know how to respond. After asking my gfs about it, they suggested i kiss his cheek. So the next time we went out, before we parted; i kissed him on the cheek, then we hugged and then he kissed me again on the neck and nearer my face, at my jawline. I didn't kiss him back cause he's kinda shy and he pulled away smiling after he kissed me. It all happened so fast. Lol. Is it okay that i didn't kiss him on the cheek again? Next time he kisses me, should i kiss him on the neck too?

We're about the same height, but he's slightly taller than i am and buff cause he does gym. Do gym guys like to be kissed on their biceps or should i not do that since we're not exclusive? How much can i do.. in relation to physical stuff? He's the first guy I've ever been physical (although, admittedly, this may not even count as being physical to some of you) with.. so, green to this.
Updates
+1 y
We aren't in a relationship because we think we're not emotionally ready for it yet. And we're both in different universities, so its a bit hard to see each other every week.
He kissed my jawline, how should I respond?
2 Opinion