it´s better to trust him than continuing to trust that psycho brother of yours, take care of that bastard with tae-kang´s help first. then you can decide if you want to belive/trust tae-kang´s feelings later.
I mean, r u read this manhwa just by scrolling it? Yigeon obv can't trust both of them. There's no a 'better choice' to pick between his brother or Taekang. For Yigeon, both just proving themselves that they can easily abandoned and discarded Yigeon as their wish. None of them can be the ally.
it´s better to trust him than continuing to trust that psycho brother of yours, take care of that bastard with tae-kang´s help first. then you can decide if you want to belive/trust tae-kang´s feelings later.