SFW is short for "Safe For Work" or in other words something you can show around others. The opposite is NSFW or "Not Safe For Work".
Hmm, not long before Kobo made the first Adventure game there was a small project called Dot-kun's Shop (loose translation at best). It started a no-name who came to a casino/hostess club where the goal is to make money and use it to improve relationship with previous games and web comic heroines. In that game, there was a dungeon exploration mini-game that later became the Adventure series. Kobo's original plan was to have a SFW version of the game and then later make a H version but that fell through when he started the Adventure series.
Kanae is an interesting one. There's suppose to be a sorta after story game focused on some time later where she has had her second child (fathered by her horny ex-boss) and I think takes place in the country side. Some of the side characters in Kanae have gotten their own side stories in the form of short web novels/comics (not sure what term to use).
I have already met the term "NSFW" (who would doubt it). It would be worth guessing that this is an antonym to SFW.
I think you mean this work (I will attach an image). If yes, then it is very sad. I would really like to see some scenes with Rikka from Busters (blue haired girl). By the way, if you follow Kobo's vlogs, you could see the art with her(Kobo attached imgur link), which I drew together with my close friend.
I'm more of a fantasy fan, so games in the Kanae category don't really interest me. Looking forward to Busters R, Gaiden Anna vol.2,3 and Moon fish. I'm also looking forward to Crystal Story Monsters. It seems to me that this work could be an alternative to "Dot-kun's Shop".