It doesn't imply they had sex or they went the Virgin Mary route. Basically Ruri's birth just happened when the two got married.
I do hope it's a Virgin Mary route thou. Japan does like sacrificing Virgins to powerful entities.
You really got that backwards, they absolutely had sex, do you want to see mother say " i fucked a dragon" to believe it? what is implied is they did not married...
Just for you, I re read the first chapter again, and the latest one again... There is no marriage,single parent house...
Secondly, there is no need for implication for anything, re read page 9 and 10...
Ruri asks "why have baby with dragon?" and as i said mother implies they did it, THEN ruri ask if it is like shotgun wedding, it is not about mother and the father get married or not, but since mother says she DECIDED to have ruri, this also strengthens that she alone raised Ruri.
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Japan does like sacrificing Virgins to powerful entities.
i am not confirming or denying it. there may be a sacrifice thing happened back then. But even if that was the issue, dragon has chosen not to eat her, but "eat" her.