Season 1

Yokoi-san is trying her best to listen in class, but she can't help but watch as Seki-kun is lining up erasers next to her. Seki-kun! Are those dominoes?!

Yokoi-san is trying to pay attention as usual. And then Seki-kun starts playing shogi next to her and it turns into something rather unexpected.

Seki-kun starts shining his desk during class. Amazed at the effect of his work, Yokoi-san finds herself being dragged into his want to shine more desks.

Seki-kun starts playing Go on his desk. Yokoi-san tries to ignore this since she doesn't know the rules, but this yet again turns into something rather unexpected.

During science class, Seki's attempts at constructing a hanko stamp from his eraser are hindered by his laid-back classmate, Akiyasu Uzawa.

Whilst participating in a disaster drill, Rumi notices that a robot family that Seki has brought into class is taking the drill more seriously than Seki himself, prompting her to take responsibility for them.

Seki creates an elaborate post office system for passing notes around the class; with many protocols that prevent Rumi from giving him a note of her own.

Seki crafts another shogi tale, this time depicting a princess who marries a pawn but is soon kidnapped.

As Seki knits in class, Rumi watches him as an expert, but is surprised by some of his maneuvers as well as the final product.

During art class, Seki plays a miniature-sized game of golf on his worn-out desk, whilst Rumi's classmate, Sakurako Gotō, misinterprets the interactions between Rumi and Seki as romantic gestures.

Rumi watches in harrowing anticipation as Seki has a group of miniature bears do a mountain climbing expedition on the back of their classmate, Takahiro Maeda.

Seki studies a set of driving rules, takes a written driving test, and then makes a driving course on his desk for a remote-controlled car, which he takes very seriously.

During water safety lessons, Rumi once again becomes invested in the diligence of the robot family, becoming panicked when the child robot is thrown into the pool by Uzawa.

During lunch break, Rumi is a little disturbed by the manner in which Seki eats the octopus weiners he made for his lunch.

Whilst Rumi is off school with a cold, Goto observes Seki as he plays a game of paper sumo involving a robot opponent, assuming he had a fight with Rumi.

As the class watches an instructional video, Seki plays a game of "Shogi vs. Chess" in the dark, with Rumi eager to help the shogi pieces as they struggle against the black chess pieces hidden in the darkness.

Seki puts on a blindfold and plays a game of fukuwarai, which soon evolves into a twisting story about family life.

With their desks pushed together in order to share a printout, Rumi attempts to ignore Seki as he performs some card tricks, hoping to prompt a reaction from her.

Seki brings various pairs of glasses to see which pair looks the best on him.

Seki draws a flip book comic in his textbook, which he even records sound effects to, leaving Rumi curious about the finished result.

Rumi learns of a surprise belongings inspection, believing it to be the perfect chance for Seki to get busted. However, she becomes concerned about the robot family, especially when Seki seems to make no attempts to hide them properly.