A creepy Charles Manson painting made with the artist's blood is awaiting an even creepier finishing touch -- the cremated remains of Manson himself -- and then it can be yours.
Artist Ryan Gillikin tells TMZ ... he created this painting using his own blood, and was able to obtain some of Manson's ashes from someone who attended the spreading of them ... back in March, near Porterville, CA.
Gillikin plans to use the ashes to fill in Manson's eyes in the painting, and then it will be complete.
Gillikin and his ash-grabbing biz partner plan to auction off his masterpiece and use the proceeds to make a monument for Steven Parent ... one of the victims of the Manson Family murders.
We'd say buyer beware, but this seems more like a beware of buyer situation.