Touya Mochizuki grows accustomed to his new life in another world. Armed with his trusty smartphone, the teenager accepts small quests at his leisure while spending time with his new fiancées: Yumina Urnea Belfast, Yae Kokonoe, and twin sisters Linse and Elze Shileska. But even in a relaxing environment, Touya is only beginning to understand the responsibilities that come with these engagements. In addition to his romantic woes, the elder fairy Lean wishes to locate the remaining pieces of Babylon, the floating island that the mysterious Professor Regina Babylon created five thousand years ago. Touya reluctantly accepts her request and seeks out the teleportation circles that will lead to the islands. However, strange monsters have emerged—possibly powerful enough to destroy the world. In order to save the second life he was given, Touya must weaponize ancient technologies to fight these monsters—all while balancing his overwhelming number of relationships.

Tousuke Rokudou is a first-year attending Aomori High, a school full of delinquents. He is often bullied by his classmates due to his incompatibility with their behavior, the only exceptions being his two good friends who are also social outcasts. Frustrated at the way they are treated, the three wish they could stand up and claim the fun, peaceful school life of their dreams. However, Tousuke's life takes a drastic turn when he receives a package from his late grandfather containing their family heirloom, a scroll said to possess the power to save him from impending danger. Upon holding the scroll, a sudden glow emanates, leaving a strange mark on Tousuke's forehead. Thinking that he's received the means to free himself and his friends from their daily treatment, Tousuke is shocked to find out that its effects are far different than what he had imagined. Although his bullying continues, he realizes that the mark from the scroll acts as a charm, capturing the hearts of delinquent girls—in particular, Ranna Himawari, the strongest of them all.

When Hayato's grandmother passed, he planned to sell her rundown café on the shore—not realizing that it was also home to five young women who call themselves her family?! Their desperation to keep the café open convinces Hayato to give it a shot...but even their best intentions might not be enough to make it work! And can he even work with these five unruly women? No matter what, he's got his work cut out for him!

There was once a man who was summoned to another world, and saved it. Of course, he became too popular there, and turned into an isekai-normie. However, that man fell into a "trap" and was forcibly returned to his original world. Moreover, he had to start over as a baby! This is the story of the way-too-fantastic ex-hero who lived as a gloomy high-schooler, as he gets summoned once again to that same other world in a very unexpected development!