When Kenichi went to summon a familiar, the book selected a succubus, one that would have drained the boy into exhaustion every day.
However, there was a spirit watching over Ryōzanpaku dojo. It was Miu's mother, Shizuha Furinji. She struke the demon, hoping to knock it out.
However, the teddy lingerie-wearing succubus hugged Shizuha and flew towards the summoning circle. Shizuha had no idea what would happen, but knew it wasn't good for her. She struggled to escape the succubus's grasp, but the demon grew tentacles and tied up the martial artist mother.
When the succubus and Shizuha flew out of the summoning circle, the two merged into one. Her clothes became similar to Capcom's Morrigan Aensland's clothes. The personality was mostly Shizuha to call herself that name, but the succubus still had enough influence to take over.
Shizuha looked at Kenichi and said, "I am Shizuha. I am yours, Master."
Kenichi gulped for a moment before he stood up. "Al... Alright, Shizuha. As for my first order... Pl-please fulfill my desires."
Shizuha brushed her hair for a moment as she gave Kenichi a lusty expression before she got on her knees and began pulling down his pants. He tried holding up his pants, crying out, "What are you doing?"
"One of your desires is for a blowjob, master. As is this," Shizuha said before she spun around, making sure her pussy was right in Kenichi's face before wrapping her legs around his head.
Kenichi let out a loud, muffled cry of confusion, unwittingly letting some of Shizuha's juices into his mouth. He was unaware that the sexual juices of a succubus had two effects when in contact with human skin. One was that they were like a super-strong aphrodisiac, which made his erection even bigger, harder and able to make multiple shots.
The second was that women would sexually desire him the moment they got his scent. It would wear off in a few weeks as long as he didn't come into contact with more succubus sexual juices.
Shizuha giggled when she got Kenichi's dick in her mouth. It didn't take long for him to cum, which disappointed her...
Right until he cummed again and again, which surprised her in a way that pleased her.
She continued giving him a blowjob until he passed out. So Shizuha took him and the spellbook into his room and placed him in his bed. She laid next to him and caressed him like a lover, cooing, "I look forward to making you go through some 'special' endurance training tonight, master."