As someone who has played quite a lot of AVNs, I'm genuinely surprised I've never heard about this one before because it quickly got into my top 10 list, which was particularly surprising considering it doesn't have any choices or other kinds of interactive aspects. While I usually prefer a bit more variety than just maledom, it does a very good job establishing a relatively healthy dynamic in that regard, with a few exceptions but they're so minor that they don't really matter. So it's not really a criticism by any means as that would be like criticising a horror movie for not being funny.
That being said, how much new content is usually added in every update? Because if it's just an hour or so I might wait until a couple more have been released as I prefer waiting longer for more content at once. But if it's 3+ hours it's definitely worth getting every new update.