Please refrain from including your headcanon in tagging unless either the artist commentary, the context of the picture or the text positively proven it. From the wiki: "Any romantic or sexual interaction between female characters, mutual or not. If it's mutual, consider adding the couple tag." In that case, both the commentary and in-image text does not given any clue about them heading that way.
are they're names posted on twitter or somewhere else? because in the commentary here it says their names are Nick and Otsugetsu. where did the name Nikutsuki come from?
The Gumroad link contains a RAR file with 52 PNG images which are the still frames of this animation. I've used APNG assembler to combine them into this APNG. The original frames can either be downloaded though the Gumroad link or alternatively extracted from the APNG.