Last time, Rentarou Zing'd with somebody else's grandmother. Specifically, Kusuri's grandmother, 89-year-old Yaku Yakusen. Noticing that she's also in the body of an 8-year-old, Rentarou surmises that she also took the immortality drug. Yaku confirms this, adding that the version she took can't be negated at all, rendering her as The Ageless. Kusuri explains that she went about creating an immortality drug so that her grandmother wouldn't die. Yaku expresses a great interest in Rentarou, and Kusuri invites her to join the harem. Yaku decides to go on an outing with Rentarou to see how he stacks up against her late husband while Kusuri stays behind to watch Pentarou on TV.
As Rentarou and Yaku go for a walk along a river, she recounts her past as a war medic creating medicines. Her husband was a soldier she met in a war zone, but she refuses to elaborate further. The two spot a patch of mugwort
growing nearby, and Yaku decides to pick some. While she discusses all the culinary uses for mugwort and how tough her childhood times were, Rentarou accidentally cuts his hand on another plant, prompting Yaku to apply mugwort to the cut. For a brief moment, Rentarou sees Yaku as her past self before she kisses his forehead and they continue onward.
As the duo return home after a long day, Rentarou tries to exchange contact information, but Yaku quickly shows herself to be uneducated in any kind of technology beyond a Tin-Can Telephone. She then explains that she only agreed to the outing because Kusuri asked her to; she feels herself too old to be dating someone Rentarou's age, and he quickly realizes that she was treating him as a child for the entire outing. However, he is still determined to show his commitment to her and decides to adopt a wild and rugged persona to emulate the "paragon of masculinity" that captured the heart of Old Lady Yakusen all those years ago.
Rentarou takes her to a nearby park, where the two of them engage in various wild and rugged activities before realizing he's only acting the part on the surface. With this, he goes in for planting a kiss on her, only to break down as Yaku returns the kiss. A coy Yaku explains that if she were to fall in love with another man, it should be for a different reason than the last man she married to. Rentarou insists he's serious about wanting to date Yaku, who teases him over the idea that he might get her to take him seriously someday.
Tropes:
- Forceful Kiss: Subverted. Rentarou tries to do this near the end of the chapter, but stops himself at the last second when he realizes what he's doing.
- Imagine Spot: Rentarou briefly sees Yaku as her past self during their outing together.
- Sunglasses at Night: Rentarou wears these while trying to act manly.
- Tin-Can Telephone: Discussed. This is the most advanced piece of technology that Yaku is able to use.
