The primary heroine of Memories Off 2nd, Hotaru is in her third year at Hamasaki High School. She often acts childish and immature, and is sometimes a airhead. Her favourite hobby is the piano. She confessed her love to Ken at Christmas, and in the OVA they're in a relationship, but she worries about Ken's feelings towards her. She appears in both of the Memories Off 3.5 OVA stories, and is a secondary character in Memories Off ~Sorekara~ who helps with Inori's feelings towards Isshu. (from wikipedia)
Ama Shigure is Asa's mother. She has the habit of drastically reducing names to cute nicknames (Asa for instance is referred to as "A-chan") and for wearing a cat-ear hat. She looks abnormally young to be a mother, and it surprises the other characters to learn she is. Ama was the first artificial life form created by the gods and devils, and is in fact actually a devil. She didn't like life and so she sold herself to the devils. Due to that, Asa has magical abilities she got from her mother.
Ren's first test subject to his hypnotism experiments. He used to be a weak and megar student who was easily bullied by the other students, even to falsely accuse Ren of beating him up and taking his money. After wards he apologized to Ren who didn't accept it as he saw it as meaningless. After Ren's hypnotism he becomes more of an open and energetic guy who is a member of the Music Club and the Journalism Club. However, Ren then used this to have him get close to Saeki for a story where he detonated a bomb he was holding, killing them both.
The recurring character throughout the Memories Off series. (Wikipedia)
Renji's mother. She looks younger than she really is.
A character introduced later in the series, the Spreader of Darkness is a young-looking man who was injured by Kane's grandmother ten years ago, and has been resting and healing for the past 87,016 hours inside of a capsule. He has the power to see into one's mind and to control one's will, as well as the ability to wield a psi-blade. Kane declares him as his arch-nemesis. He is actually the clone of Stargazer, the head of Nightmare. In episode 25, he summons Millie to kill Kane, revealing to her that the two are related and that her real name is "Millennium Feria Stargazer."