A little secret [Soukoku / omegaverse]

Introduction

IMPORTANT READ PLEASE !!

This story is an omegaverse !
Dazai : omega (bottom)
Chuuya : alpha (top)
Side ship :
Atsushi : omega (bottom)
Akutagawa : alpha (top)
(Other character second gender will be explain on the chapter)

In my omegaverse :
Omega pregnancy is 6months long.
Heat appear 1 time each month, 3-7 days (like period for woman but without the blood)
Rut appear every 3 month, 1-2 days.
An alpha can mark an omega permanently or none-permanently and if they both consent they can bond together.

I don't see a lot of Soukoku fanfic bottom dazai so I decided to make one ! ;)

If you didn't read the description read this :

Dazai and chuuya started dating while they were in the port mafia at the age of 16 years old. At chuuya 18 birthday dazai and him did it , their first time. Some weeks after chuuya birthday.... oda died...
Dazai left the port mafia, to respect Oda's will.

While they talk : sentence
While they think : think
Author note : (author note)

Tw :
Mori
Abuse / p€dophilia
Smut ? (I never write smut of my life so it's gonna be my first time writing smut..)
Mpreg (sorry if you don't like mpreg)
Soukoku ( ofc they're gonna be Soukoku why would you come here if they wasn't)
Angst (I hate angst so it will be soft angst and happy ending because I hate sad ending)

( I will say it in the chapter if one of those thing appear in it and English isn't my native language so they are gonna be a lot of writing mistakes )