Honestly? Koneko's personality is fascinating because it's built on layers of repression. On the surface, you've got this deadpan, dismissive kuudere who calls Rias 'President' and Issei 'Perverted Hyoudou.' But that's just the shell. Her trauma from her sister's betrayal left her believing her own existence was a mistake, that her power was only for destruction. That core belief dictates everything. She keeps everyone at arm's length initially, not because she dislikes them, but because she's terrified of hurting them or being rejected again.
The real impact is seen in how her relationships evolve only as she slowly opens up. With Rias, it's a guardian-ward dynamic that shifts into genuine, fierce loyalty. With Akeno, there's this complex mix of rivalry and unspoken understanding as fellow victims of trauma. But it's with Issei her walls truly crumble. His relentless, idiotic kindness and acceptance—seeing her not as a monster or a tool, but as a cute little sister—gives her a new framework for her self-worth. Her blunt insults become a form of affection, her quiet presence a sign of deep trust. Her personality forces relationships to be earned slowly, but once forged, they're unshakeable. That's why her moments of vulnerability, like asking Issei to hold her, hit so hard—they're proof of how far she's come.