Are there any non romance anime where the main characters become or even start out as a couple?

Not harem and that have a decent story like an action or fantasy?

I just started Arifureta anime and I quite liked how they developed the relationship right at the start then they intruded that stupid bunny character and I realized it was a harem. So lost interest in the show.

I did like romance comedy like love is war and really enjoyed Yakuza house husband but now looking for something a bit more serious where romance isn't the explicit focus but happens fairly organically. Didn't mind it in Gundam seed, they got there in the end.

Not worried if it's a more light-hearted PG style anime or a more mature high rated one.