She cons thirty-something year old men pretending to be an easy fling and murders them. I guess that's the pattern. All 3 victims were most likely also her exes, including the last who was a married man with a son... the first dude in particular looked like a stereotypical nanpa pickup artist, he hit on and picked her up at a beach after all.
Not sure she's gonna take Arata's bait, he's already stretching it bullshitting his way in without a marriage registration paper like she first demanded.