I know people love this game, and it's steam deck starter kit material. But HoloCure: Save the Fans is infinitely better.
This game is basically a brain dead mind numbing experience. It's just move, that's it. Move the dude. He attacks. The end. Move some more. Get enough upgrades so you don't have to move. The whole game is basically a slot machine of dopamine where the more you win the less you play it and the more you just are hitting "OKAY" to move onto the next upgrade reward.
I can see why it's addictive, but I think it's in an unhealthy way and I'd encourage people that like this game to try HoloCure if you want a better version of this experience that doesn't insult you as a human.

This YNFG is what nightmares are made of.. I mean, look at my profile picture, surely you can probably tell that I look up at this game very highly. Give it a shot if you can if you are looking for something else to play after Yume Nikki.

.Flow takes everything you are probably comfortable with in Yume Nikki and flips it on its head and it is an innovator for many fangames after it. It has lore, horror, and intrique. You have rust to be careful of and the in-game monster known as Kaibutsu to worry about as they are out to kill you and are more terrifying than Yume Nikki's Torriningen as this game wants to try and kill you if you aren’t careful. I love this game and I hope if you are looking for a game to play after Yume Nikki that you decide to give .Flow a chance. You will not regret it.