Board Thread:Questions and Answers/@comment-27524978-20160114233341/@comment-27560522-20160116233359

Flowey doesn't feel anything for his parents anymore - he tried to, for a long time - but he just couldn't. So he gave up on them. Killing them is nothing to him.

Chara, however, is the one he's been the most connected to - and perhaps still is, since they shared souls, and even died as one.

1. - In a pacifist route, Chara remains passive throughout. So he couldn't sense any sort of influence from Chara in Frisk, at least not yet. I suppose it was more difficult to pick up?

2. Omega Flowey lacks a critical component in that state in order to become a complete being - for a fusion to be perfect there must be an equivalent power of monster SOUL paired up with human SOULs.

Flowey himself has no soul at all...so Omega Flowey was lacking monster SOUL power. And thus he became a corrupted being.