I'm looking for a manga about ghost / creature in a dream that catches people, and when they do, the unfortunate person would also be killed in real life.
I think the protagonist friend was the one who got killed in the dream. He tried to help his friend (they having the same dream that they were in school and the creature tried to capture them) but failed and when he woke up, he found out that in real life, the friend was committed suicide (because the monster killed him in the dream).
Anyone know what manga that I'm talking about? If I'm not mistaken, the first volume cover is the dream creature that looks similar to ajin from another manga (again, if I'm not mistaken, because I've read it years ago).

Is it Yumeoi?