Does anyone know which アニメ this is?

I apologize in advance for the vague explanation I'm about to give.. I watched a single episode of this アニメ about a 年 前 and I now want to watch this anime, but I haven't the slightest clue what it was called...

Basically what happened in that episode was, a person was living in an empty room with a painting on the wall. The painting was of sakura trees, but the trees were bare. The branches started growing out of the painting on to the walls and kept expanding until branches covered the entire wall; and as they were growing 日 によって 日 the person living in the room became weaker and weaker. It turns out the branches were growing using the person's strength.. または life.. または soul または whatever helped it grow. Anyway; the person went to ask someone who is presumably familiar with the situation, and that person said, if this continues あなた will die.
At one point, toward the end of the episode, a girl crawling out of the ceiling... and at the end of the episode, the painting on the ウォール had a person in it, hidden among the trees (whereas at first it was a painting of bare trees only). I think there was also something about the sakura trees blooming...

Alright. I apologize again for the crappy explanation.. Does anyone know what アニメ this is?