[ While Megumi doesn't mean to eavesdrop, he's an observant person by nature, so he can't help but overhear and note this stranger's musings. The Strike Hawks? Some sort of group or gang he's involved with? Time will tell if he gets curious enough to ask. He is curious about the fortunes or others, however, if only because he'd like to know the likelihood of them becoming true. In other words, he has the same questions that Chrome does.

Paper in hand, he glances at it once more.

"The ones you love will bring you misfortune." ]

... It's too vague to know for certain. But these things are usually meant to be vague so we assign our own meanings to them.

[ Despite coming off slightly skeptical, he can't help but feel unsettled by what he's got in his hand. ]