27(Crossover)

An Au where Fem Sanzu and Mikey were dating till their last year of high school when Mikey met Takemichi(or another character, canon or otherwise) and fell for them.

Sanzu was broken hearted by this but respected Mikey's wishes as she saw no reason to force Mikey to stay with her if he didn't love her anymore even if she had just recently found out that she was pregnant(as condoms do not always work).

Not wanting Mikey to know about the baby and force himself to stay with her, Sanzu asks Takeomi to transfer her to another school in another city as she wanted to attend the university of that city.

Sanzu finishes high school despite carrying and giving birth to a healthy baby boy who she named Shin, she had no one by her side as she knew her siblings would tell the Sanos about the baby which she did not wish to happen so after finishing high school and finding a job she cut contact with her family.

When her baby was around 2 and half, Sanzu met a man named Tasuru Ando who while she did not find attractive he offered her a place to stay and stability to raise her son as long as she married him and acted as his bodyguard since she had been working random jobs as a bodyguard(as she was trained in martial arts by Grandpa Sano).

Unfortunately, two years later Sanzu got gravelly injured while protecting Tasuru and ended up in a coma. Feeling guilty about it but also not wanting to deal with raising Shin alone, Tasuru leaves them in his old friend Asakura's care.

Things follow Sakamoto Days canon except that Shin visits at least once a week his mother who is still in a coma with Asakura working to find a way to wake her up.

Mikey, who still formed Bonten but the one they left Sanzu for is their spouse and second-in-command, was one of the people contacted to try and get rid of Sakamoto but first he decided to see how Sakamoto was doing and why they would wish to get rid of someone who was retired so imagine his surprise when he meets someone who looks a lot like him when he visites the Sakamoto Store.

While deciding to not agree to try and kill Sakamoto, Mikey can't take the image of Shin from his mind so he sends Takeomi to investigate if Shin could be one of his half-siblings or even the child of one of his half-siblings but when Takeomi comes back empty handed as it seemed like someone erased Shin's past, he could only try and get close to Shin to find out.

So Mikey became a frequent client of the Sakamoto Store and tried to get close to Shin with some luck but not enough to ask him about his family.

It isn't until the fight with Mr. X that Mikey, who is helping them with Bonten, hears Asakura saying that Shin could not die or lose an important sense now that he found a way to wake his mother(who he referred as Haruchiyo and reminded him of his ex-girlfriend).

So they win, or so I suppose since I haven't read the manga and am simply going by a video I saw on YouTube, and things go back to normal except that Shin disappeared for a month or so before he came back accompanied by a woman that only Bonten members and Aoi knew(Aoi because Sanzu saved her from a stalker/pervert before) who he proudly presented as his mother to his friends.

The reactions to this and anything else that may happen(or any changes to the canon of Sakamoto Days or the au) is up to the writer.