I wouldn't say that its relationships are 100% lifelike or anything, but they are more heartfelt (beyond the constant "I love yous" thrown back and forth; which, again, deus ex heartchina) and don't involve the objectification you would imagine from a show about dating 100 women. 100 Girlfriends leans heavily towards affection as opposed to lust, and this is a key decision. Doing so blunts the negative impacts of fanservice and actually enables it to serve as a tool for characterization! The use of fanservice primarily as a joke also makes it, frankly, more acceptable. I don't even feel weird about showing it to my partners, whose most notable prior exposure to anime was Yuri on Ice!
I watched it dubbed until I caught up, and found interesting differences between dub and sub which actually make me want to go back and rewatch a few episodes about literature with subs, because that threw me for a loop. However, I will say both are absolutely fantastic.
There are a lot of great jokes tossed in here. Other comedy shows I've watched recently have definitely incorporated more modern meme culture, but I think 100 Girlfriends hit it out of the park. With regards to how it stands alongside harem shows? Honestly, it doesn't matter. It's not really a harem show: 100 Girlfriend is an exercise in watching the crazy polycule turning and turning in a widening gyre, but the center, Rentaro, is 800% committed to hold, and so the end will not come.
