Akane no Sora ni Tsuki o Miru

A young man with the power of healing leaves his hometown and starts to live alone in the city. He occasionally reunites with the childhood friend there which revives nostalgic memories. But one day he is attacked by a woman with a sword. He manages to escape, but days get filled with anxiety. He soon notices a bruise that begins to spread throughout his body. Where does it all lead to?

[From vndbreview]