Episode 1
The Special Circumstances of My Bathtub
High school student Tatsumi lives alone. One day he spots a person while walking by a river. He approaches the figure and discovers a beautiful man collapsed on the ground.
Episode 2
The Severe Circumstances of My Household Budget
Wakasa begins living in Tatsumi's bathtub. Just having a merman live in his home is difficult enough, but another major problem arises: the living expenses including water for Wakasa!
Episode 3
The Circumstances of Wakasa's Friends: Takasu Edition
One weekend morning as Tatsumi heads to the bathroom with breakfast, he hears lively voices coming from inside.The puzzled Tatsumi opens the bathroom door and discovers a mysterious octopus? No, it's Wakasa's friend Takasu.
Episode 4
The Circumstances of Wakasa's Friends: Mikuni Edition
Tatsumi informs Wakasa and Takasu of a rumor about a ghost appearing in a nearby park. Behind Tatsumi, a mysterious white object appears... The white shadow tells a surprised Tatsumi, "Nice to meet you. My name is Mikuni."
Episode 5
The Halloween Circumstances of My Household
A witch, a vampire, and a mummy... From the darkness, Wakasa, Takasu, and Mikuni appear.When Tatsumi sees Wakasa dressed as a witch, he wonders why. When Mikuni declares, "Trick or Treat," he realizes it's Halloween, but he tells the trio he has no candy. The watchful trio pounces on Tatsumi with a tickle attack! What will happen to Tatsumi? Will Wakasa and his friends acquire any candy?
Episode 6
The Circumstances of My Bubbles
Wakasa reads his magazines as usual. He had become obsessed with the female fantasy of taking a bubble bath. When Tatsumi enters the bathroom, drags Wakasa out of the tub. Wakasa doesn't understand.
Episode 7
My Sibling Circumstances
The doorbell rings. A panicked Tatsumi says, "She's here! I'm counting on you," and Wakasa responds by giving him a thumbs up and saying, "Leave it to me!"
Episode 8
The Trendy Circumstances of Modern Men
One day at dinner after Wakasa is finished eating, Tatsumi finds leftover bell peppers and carrots on his plate. When Tatsumi asks why he doesn't eat vegetables, Wakasa responds being a carnivore is the current trend.
Episode 9
My Naked Circumstances
Wakasa is shocked when Tatsumi leans over the tub and announces it stinks. Tatsumi cleans the tub responsible for the odor and transfers Wakasa to a children's pool. Saying, "Brother, tell me if you're using the pool," Kasumi mistakes Wakasa for Tatsumi and hugs him.
Episode 10
The Circumstances of Wakasa's Friends: Maki Edition
Some schoolboys are making a commotion in front of Tatsumi's apartment. They leave immediately when Tatsumi calls out to them. Looking down, Tatsumi discovers a conch rolling near his feet.
Episode 11
The Seven Transformations of my Bathtub Circumstances
When Wakasa asks if something good happened, Tatsumi shyly admits his manager gave him a raise and allows Wakasa to splurge a little. Wakasa grins at Tatsumi's offer to splurge, and Tatsumi buys Wakasa a massive amount of milk. While Wakasa enjoys his milk bath, Mikuni, Maki, and Takasu arrive...
Episode 12
The Circumstances of Wakasa Staying Home Alone
Wakasa gets nervous when Tatsumi is late coming home and gets out of the tub to look around the house, causing a mess and nearly drying out. When Tatsumi comes home, he thanks Wakasa for worrying about him, but makes him promise not to get out of the tub next time, or else he won't give Wakasa the cake he brought with him.
Episode 13
The Circumstances of Wakasa's Employment
Wakasa worries that Tatsumi may kick him out after watching a man complaining about his partner's moocher tendencies on TV, and asks Tatsumi to help him find a job. Because Wakasa has nothing to put on a resume, Tatsumi recommends that he enter by-mail sweepstakes, but Wakasa is unable to write kanji and Tatsumi must teach him. Wakasa fills out stacks of postcards, but is shocked that he will not get to see the contest results for a month. Tatsumi reassures Wakasa that he doesn't have to worry about being kicked out, because they are friends. Wakasa mainly enters contests to win free meat, but what he receives at the end of the month is a scarf, which he had been aiming for to give to Tatsumi. During the credits, Wakasa's friends come over for a New Year's party, and Kasumi also has a brief appearance wishing her brother a happy new year from her own house.
