銀魂喧嘩ップル|沖神 ~休み中 | hiatus~

This one deserves a special post of its own.

I highly suspect that the one who wrote this greeting is this person, as the art style looked veeeeeery familiar.

Her name is Gon, a low-key doujinshi-ka who happens to be good friends with Nakajima and Satomi, two very well-known okikagu doujinshi-ka.

Her message says:

No matter how many times I give my greeting, this guy always stay the same age [18].