Catharsis is a short, diceless game with a sort of poetic structure and layout. You play by having a conversation with structured pauses, and optionally there are flowers.
The conversation is...sort of just a regular conversation, although depending on how seriously you take the topics, you may end up some more serious places. In that sense, Catharsis is a bit of a stone soup. It's a prompt, and you contribute its meaning yourself.
Overall, I'd recommend this to anyone who likes conversation games, or games with a poetic feeling to them.