Warning! Spoilers ahead for Dandadan chapter 47!
A group of ostensibly random characters who originally played a minor role in some one-off side story just came back with a vengeance to help one of the main protagonists in Dandadan fight against a powerful enemy.
Even before their arrival, the battle they would later join already massively diverged from the norm - if anything in Dandadan can even be remotely considered normal. The spirit medium Momo Ayase - who usually fights alongside her friend Ken Takakura aka Okarun - is battling her Evil Eye Yokai-possessed former boyfriend Jiji with the unluckiest allies. The first is a woman who originally tried sacrificing her to a giant death worm and the other is a random monk Momo met once before but who's apparently her grandmother Seiko's student. Meanwhile, the Turbogranny-possessed Okarun is unfortunately out for the count.
As victory becomes increasingly unlikely, these random reinforcements suddenly arrive from a UFO that miraculously appears out of nowhere, descending amidst the fray in chapter 47 by mangaka Yukinobu Tatsu. First, the so-called Dover Demon jumps down to aide in the fight before Momo's oddly sexual and lazy grandmother flies down on top of an anthropomorphized anatomical model named Taro. Before now, the Dover Demon and Taro were believed to be nothing more than minor characters who served as the main focus of random side missions. The Dover Demon was originally a gig fighter and fought against Momo and Okarun with the Serpo, an alien race that has been obsessed with stealing certain body parts from Momo and Okarun. The initial purpose of the demon's introduction was basically as a means to provide a hilariously clever explanation about why aliens are oftentimes portrayed in pop culture as cow-stealing robbers. Basically, the heroes Momo and Okarun eventually befriend their former enemy to help him with his son's blood transfusion. And cow's milk is the key.
Meanwhile, Momo and Okarun's past dealings with Taro served as a means to provide an incredibly unique take on what constitutes a star-crossed lover - with the series' now proprietary supernatural twist. One human anatomical model named Hana was in a dumpsite while the other (Taro) was bound to his school's science classroom and could therefore only visit her at night. Together, Taro, Hana, and the Dover Demon represent each defining aspect of Dandadan: the supernatural (yokai) and alien invasions. Although Dandadan is essentially a string of ostensibly isolated incidents, both of the storylines that starred these particular characters originally felt especially unrelated and created the impression that each of these instances was just a minor albeit highly entertaining way of world-building.
Meanwhile, the addition of Momo's grandmother Seiko just serves as major fan service since she's incredibly sarcastic to an amazing degree. Until now, Seiko has never participated in any of the missions that she has assigned to her granddaughter (mostly due to how her power manifests in relation to where she lives). So, getting to see her fight will add more to her already intriguing depiction. In addition to making the ongoing battle much more entertaining in chapter 47, the inclusion of these originally minor and one-off characters is not only proving that earlier events that seemed completely random at first actually aren't but creating a larger sense of togetherness and interconnectivity in Dandadan's very unique and highly inspired world of yokai and aliens.