in the worst case; just in case; by any chance

perhaps

a quite rare case - literally, one for ten thousands.

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend

he; boyfriend

next..., coming...

to come (toward the speaker/writer) / (specifically, of a sensation) to come and stimulate / (と来たら (to kitara)) when it comes to

potential of 来る (kuru, “to be able to come”)

a surname, especially of those descended from swordsmiths arriving from Goryeo around the mid-Kamakura period