Kimi to Unmei ni Tsuite no Hanashi ga Shitai

Even if we're both betas and even if we're not a fated pair, it'll be fine. Our relationship won't change, ever.

Hibiki is a salaryman who has been living together with his high school sweetheart, Koushiro, for 10 years. When they had just met each other, they were convinced that they were a fated pair, but their gender tests revealed that they were both beta. Even though other gay couples can be blessed if they are a "fated pair," it vexes them they can't even hold hands in front of people. They tell themselves that if they love each other, all will be fine, but trivial things make them more anxious each day... But they hear about a misdiagnosis of the gender test one day...!?

(Source: Tokuma Shoten, translated)

Note: Includes one extra chapter.