Shimeji Simulation is a story about a girl who spent two years in a closet. After emerging, mushrooms have grown from her head. It's a really bizarre story. I really like Tsukumizu's art and stories, and it has surpassed her previous work, Girl's Last Tour, for me.
Charcoal Feather Federation
There are many people who would dislike Haibane Renmei. While I love it's strange atmosphere, slowing pacing, and air of mystery, many people would find it unsatisfying and dull. It is one of my favorites despite how some people may viewed it as flawed.
OFF by Mortis Ghost has influenced everything I've ever written since playing it. The bizarre world, the strange art style, and the unique story is always on my mind. I used to play it once a year to re-experience what it felt like all over again.