Sharing is Caring is an NTR focused VN following a married couple and their explorations into different flavors of NTR.
No, the NTR is not avoidable. In Sharing is Caring, you basically choose whether you want netorare, netori, or netorase and then run with it. There is a missable scene halfway through if you try to mix and match, so choose one and stay the course. Replaying is pretty quick with the skip function anyway.
The upside of the game is the scenes are fairly hot. The character models are pretty average, but there's definitely been thought put in to the circumstances around the porn. While it's basically just porny nonsense, it does that well.
The downside is it's pretty soulless. The characters have little personality, being little more than their relation to the main character. The story basically just links the sex scenes together, just telling you how it's going to be before you choose what flavor of NTR you want. It's not outright awful, but if you don't like the scenes, there's nothing else here.
Overall, it's a four edging towards a three. If you're an NTR fan who likes Koikatu models, this game should entertain you for a time. If you're lukewarm on either however, feel free to skip.