How to make her mine?

Advice does work!

"This guessing game is so boring. Fyodor, your choice of games sucks just like your personality." The smirk never left Dazai's face as he continued to nag his jail buddy for playing a different game. But Fyodor knew better than to underestimate even the slightest changes in Dazai's expressions. After all, the Demon Prodigy was the reason for his current situation.

"Do you have that much free time to waste around while your precious ADA is on the verge of ending? just like a setting sun?" But Dazai wasn't affected in the least. And so here they are now, in the prisons, getting advice from each other about their supposedly 'Biggest Concerns' in life. A 'Clown to Clown' conversation for people who were supposedly monitoring them. Well, sucks for them for not being on the same level as them. Nonetheless, to say, they were at least enjoying this game, for now.

"I'll go next," Dazai said with a very serious expression as if he was going to ask for advice on some very serious matter. "The café hostess isn't swayed by my attempts to woo her. What should I do?" Dazai looked drop-dead serious, while Fyodor was trying hard not to burst out into laughter. He had a reputation to uphold, thanks.
"Well if you make her lose her job and her House, and trick her Family into abandoning her, then she'll come and cling to you." Fyodor managed to look completely serious.

Clang!

The loud sound disrupted their funny advice session but as Fyodor glanced in Dazai's direction, the man had a devilish smirk plastered on his face. "Aha, I see! I already did that, but I don't think she got my message. She hates me for all I know."

All of a sudden, the wall of Dazai's cell crashed making a loud sound. The alarms blared through the building alerting everyone about the situation. But to Fyodor's surprise, Dazai didn't look fazed, not even a little bit. Instead, the man was now smiling.

"The most sensible thing to do here would be to ask me out like a normal person, Shitty Dazai! But I can't expect normal from you now, can I?" An irritated voice boomed through the ruins of walls, making the figure clear as it approached closer to Dazai. The red glow surrounding him made Fyodor's eyes wide in realization.

"Chuuuuyaaaaa~ I was waiting for you. Didn't you miss me? And Chuuya wants me to ask him out? Am I dead already?" Dazai was looking at the man in front of him with sparkles in his eyes.

"Shut up Osamu! Thanks to Fyodor, now I know why you did what you did back then. And cafe hostess? Really?" The Port Mafia Executive was clearly unimpressed at Dazai's antics.
"Chuuyaaaaa~ That's not important. Let me ask you out, now that you know how I feel. I have already apologized to you even before for my past actions. That place was toxic for you. Please forgive me, Chibi."

"Now is not the time! Move your lazy ass and come out, we don't have much time!" If it wasn't for his feelings for Dazai, Chuuya would have strangled him right here. Forget that, he wouldn't have bothered to rescue the bastard from the jail, to begin with.

But Chuuya had liked Dazai, and he had kept those feelings to himself for all these years cause he was scared that his feelings wouldn't be returned. But hearing that lamest conversation just now, things just clicked and Chuuya couldn't help but smile to himself. But he wasn't going to let Dazai have it so easily. Chuuya would make sure of that. Dazai had it coming after all the shitty antics he pulled of to make Chuuya his. "Come on, let's go." Chuuya pulled Dazai by his arm once he was freed from the chains.

"I demand ten fancy dates and a proper proposal. Plus no complaints about your work from ADA. I know Kunikida and he will definitely inform me if you are slacking off during work. After that, I will think about it." Chuuya couldn't be crueler to Dazai if the brunette's horrified expression were to say anything.

"Chuuuuyyyaaaa! Chibi is so mean! I said I am sorry. Why would you torture me like this?!" Dazai all but whined, clinging to Chuuya and the executive just rolled his eyes at his now boyfriend.

"It's only fair after you straight off ditching me for 4 years!" Fyodor watched the duo bicker, still surprised by the whole exchange.

The group called Sheep, Chuuya getting abandoned by them and later on joining Port Mafia, it all made sense now. But to think Dazai would actually do these things to make Chuuya his was just unbelievable. It's not like Fyodor was giving the advice seriously, but Dazai had to be a true sadist to do those things for real.

"Ah, Fyodor kun~ I think the advice actually works in the end!" Dazai winked at him, pulling Chuuya closer.
"Please don't go on giving this advice to people who actually ask you for it. You will ruin their lives. It worked only cause though your plan was shitty your intentions were pure Osamu and well also cause the guy was Nakahara Chuuya." Chuuya rolled his eyes but planted a quick kiss on Dazai's cheek nevertheless.

And Fyodor, well he watched the most vicious duo in the history of Yokohama, bickering like a married old couple as they walked out of the cell.