|I hope I get to be forever with you, Retsy...|
— Tadano to Retsuko
Tadano is introduced to Retsuko when he meets her at a driving course and over time the two develop a romantic relationship, but they later break up owing to their different perspectives on marriage.
Tadano has the appearance of a donkey. Tadano is tall and slim with a rounded head and a long-ish rounded snout. Tadano has pale lilac fur with light lavender fur on the tips of his ears, curly periwinkle hair, long ears and blue, tired looking eyes with often large pupils and a skewed mouth. He has a long, thin tail that is the color of his fur and ends with a tuft the same color as his hair.
Tadano is often shown to sport a long sleeved black hoodie with a white hood and collar, or a long-sleeved light gray hoodie with a periwinkle hood and collar. He is only seen wearing a proper suit once in the show when he visits Chararyman Trading to try and show off his new A.I program. He wears a full black suit with a white shirt and a blue tie. He is also seen to be left-handed when autographing for Haida.
Tadano comes across in the earlier episodes as someone who never really grew up. Despite supposedly being Retsuko's age, Tadano comes across as very teenage-like from his overly relaxed and slouched posture, use of much more casual slang (affectionately calling Retsuko by the nickname "Retsy"), calm voice, and tired yet amused looking eyes and expression. He even decides to give up trying to get his driver's license.
It is later revealed near the end of the seventh episode that he is not exactly who we and Retsuko think he is. He turns out to be an up and coming Tech mogul that is well versed in technology, and is much more intelligent than he first seemed. It is also revealed he seeks to push beyond modern capitalism and wishes to restructure society to allow people to pursue their own interests, without having to work a menial job. He's simply an overall chill dude who doesn't have the intention of settling down, and even though he had unintentionally hurt Retsuko's feelings in his brief romance with her, he is still respectful of Retsuko's choice on breaking up with him.
ENI-O is an AI (artificial intelligence) created by Tadano.
Tadano and Retsuko developed a romantic relationship stemming from them meeting while attending their driver's license classes. Nonetheless, he unintentionally caused the insecure Retsuko to become separated from her family, friends and workplace. Eventually, they broke up at the end of the season as Tadano does not share Retsuko's desire to get married.
Haida and Tadano have formed a bond over their mutual rejection by Retsuko.
Tadano helped Gori with her app's code, and the two seem to have bonded over working on it together.