Rin is super cute. Haru must think so too ;) And even though I personally ship Rin with Nitori, for this chapter I'll pretend I ship him with Haru, just so it'll be a bit easier. Cuz honestly, I feel like is Rin did anything at all to try and get Nitori to sleep with him, Nitori would just be like "A'ight." But in a much more kawaii way.
So anyhow, Rin's Dere type... hmm.... 75% Tsundere, and 25% Dandere? Sure. That sounds about right.
~~~~Example~~~~
Rin: Haru, race me. (Scary voice)
Haru: No thanks.
Rin: (Clenches his teeth) Tch! Whatever.. I didn't wanna race you anyways.. (Blushes slightly)
~~~~End of Example~~~~
So, this example shows the Tsundere side of him. I didn't know how to incorporate the Dandere in him, but I just feel like it would be in there.. I don't know... I always picture him being all cute and lovey-dovey.