The monster under my bed

Every young child has a monster living in their closet or under their bed at some point. But they all grow out of it at some point.
Muichirō is known to have a hyperactive imagination. So when he thinks there's a monster under his bed that also lives in his closet, no one believes him. This leads to Muichirō beginning to doubt his own credibility. Is it that hard to believe him?
Before he knows it, dreams with seemingly no meaning behind them become nightmares too real to be true.

crdts.Blixarchiviumofthoughts