Virgin Mary style? Or her and Cassius did the devil's tango on their "wedding night", we don't actually know what transpired between the two as the cut back to the wedding of Seria and Rouche.
*the scene
The devil's tango !!! Lmaooo
Yeah maybe we don't know
It's the only possibility I could come up with because there is not another person I can think of that might have slept with Lina other than the ogml who is Rouche's cousin sense he looked like Rouche almost to the point of being twins
But that is a huge stretch to go off from
We will see by whom later
my bet is on the black magic thingy
Lmaoo!! Pregnant by whom ??!!