Kusuri invites Rentarou to her home, owing to her father wanting to meet him. The duo arrive at the house, where they are greeted by Kusuri's mother. Remembering that his harem has Hahari and Chiyo in it, Rentarou braces himself for a Zing with Kusuri's mother and... no Zing. Relief that Kusuri's mother isn't one of his soulmates quickly gives way to shock when he realizes the woman has the body of a child. Kusuri explains that she took the same immortality drug as Kusuri. Her father then shows up at the door, also in a child's body, same story as his wife.
The family members formally introduce themselves to Rentarou before Dad confronts Rentarou about the other girls he's dating alongside his daughter. Kusuri beckons them inside, where Rentarou and the Yakusens share a cake and tea. The living room is filled with all sorts of drug making apparatus and a large vat of neutralizer drug. The parents explain how the family has been making drugs for generations, as well as the first time they met and the first time Kusuri made her own drug.
Suddenly, the parents collapse to the floor spasming, whereupon Kusuri realizes their tea had been drugged. A pharmaceutical spy emerges from the shadows and offers to provide the antidote in exchange for Kusuri working for him. Rentarou tries to stop her, but the spy threatens him with a gun. Kusuri acts as a Human Shield for Rentarou, who tries to work his way to a set of drugs on a nearby table. The spy shoots the vials before Rentarou can reach them before threatening to shoot Kusuri in a non-vital area. Rentarou acts as a Human Shield for Kusuri, to the others' confusion.
Rentarou refuses to allow Kusuri's drugs to be abused for the spy's purposes, prompting Kusuri to break down crying in indecision. As she and Rentarou start making out, the spy loses his remaining patience and starts blasting away. The bullets get stopped by Kusuri's father, who has taken on a larger muscular form. He pieces together what Rentarou had planned to do by having the spy shoot the drugs on the table before punching the spy through the roof. Rentarou confirms that he did indeed trick the spy into shooting the vat of the neutralizer drug to counteract the poison, thereby undoing the spy's Poison and Cure Gambit.
The family thanks Rentarou for saving them, and as Kusuri and Rentarou share a kiss, another person arrives at the house, whom Kusuri identifies as her grandmother. Rentarou introduces himself to the newcomer and—ZING!!
Tropes:
- Artistic License – Biology / Artistic License – Gun Safety: The spy, irritated that Kusuri insists on shielding Rentarou, threatens to shoot her in a "non-vital" place like her leg. There is no such thing as a "non-vital" place to shoot someone. The leg has several arteries that could get hit, causing one to bleed out very quickly. Luckily it doesn't come to that.
- Bait-and-Switch Character Intro: With Hahari and Chiyo having happened, Rentarou wonders if Kusuri's mother will be his next girlfriend,... but she isn't.
- Batman Gambit: Rentarou surmises that the spy used a drug to poison Kusuri's parents and pretends to need some drugs from a table that would cause the spy to shoot at the vat of the neutralization drug, so that the parents would be restored without Kusuri needing the antidote.
- Dramatic Irony: Kusuri's father doesn't think a 15-timer like Rentarou would understand the idea of true love, like the Love at First Sight he and his wife experienced. Rentarou had already experienced the sensation 14 timesnote and goes through it a 15th time with Kusuri's grandmother.
- Human Shield: Kusuri and Rentarou serve as this for each other.
- Meet the In-Laws: While Rentarou had met some of his other girlfriends' parents before,note this is his first proper meeting, as Kusuri takes him home to meet her parents, who like her usually resemble eight-year-olds due to taking her immortality drug. It goes fairly well, although Kusuri's father isn't too happy that his daughter is dating someone who has 14 other girlfriends. At the end of the chapter, he meets Kusuri's grandmother Yaku, who also looks eight years old thanks to the immortality drug, and turns out to be his 16th soulmate.
- Poison and Cure Gambit: A pharmaceutical spy poisons Kusuri's parents to coerce their daughter into working for him, clearly planning on using her drugs for unsavory purposes. Rentarou figures the poison was a drug, and he tricks the spy into shooting a vat of the neutralization drug to restore the parents.
- Shout-Out:
- Kusuri and her parents are called a "Kusurylvanian family".
- Renatarou compares Kusuri's father to The Incredible Hulk upon seeing just how muscular he is.
- A Twinkle in the Sky: The spy after getting punched through the roof by Kusuri's father.
- Vile Villain, Saccharine Show: The pharmaceutical spy is the first villain in the manga to actively threaten another person's life.
- Wham Shot: Double Subverted. Kusuri invites Rentarou to her home to meet her parents. Remembering how he got Zing'd with Hahari and Chiyo, Rentarou braces himself for a Zing with Kusuri’s mother... and nothing happens. But then, Kusuri’s grandmother comes home and—ZING!!
