Secret's Withheld in The Flowers - Six Flowers Head Canon (Dark)
Aqua is the manifestation of Asgore's bloodlust as well as childish nature. Having heard all the ways he would make the one who caused him so much pain pay while also hearing all of the fun games Asgore enjoys doing and has done with Kris and Asriel while they grew. Thus explaining her child like wonder and personality as well as her obsession with knives and stabbing.
Blue is the manifestation of Asgore's more rational side and stability. Whenever he admits to himself that he's letting his obsession with the event, the one behind it, and wanting to prove himself consuming him. That he can simply just, let it go and try to proper fix things with his wife instead of fixating on proving he was telling the truth. Hence why Blue is the most mature and emotionally stable out of them. Often able to see through people with ease and solve most problems between the other flowers.
Green is the manifestation of not words spoken, but the one's not. Whenever Asgore is simply silent, though still oh so kind. Letting his actions speak for his character either though giving flowers away for free or offering treats to young children within his shop. The days where Asgore simply just doesn't want to speak, to let people see how overwhelmed he really is. This is why Green simply decides not to speak, letting her actions and body movement show what she is thinking or feeling. It's also why when things become over stimulating she simply shuts down.
Orange is the manifestation of Asgore's pure, raw, and uncontrolled emotions. The days where he's just, done trying to hold it all back and act like he is put together. Either flying into blind fury by being no where closer to the truth and thinking too much about what it's lost or just breaking down into tears that he can't ever find the answer's to get everything back. Not to mention all the time he's heard those whisper about the event when they think he doesn't hear. Hence why Lyra is so quick to anger or tears and attempted to hide herself at first. No to mention paranoid everyone is simply talking negatively about her when they say anything.
Purple is the manifestation of Asgore's obsession for order, structure, and detail. Whenever Asgore locks himself in his room and just dives back into everything he knows again. Going over every little detail, any small bit of evidence, and even the most simple statements. Again and again, over and over he'll go through everything as thoroughly and carefully as possible. Making sure it all stays neat and organized. This leading to Seth's obsessive need to have structure and order, to have their plans followed to the letter without any question or doubt. It's also why they're quick to freaking out and nearly breaking down whenever things don't. They seek stability through order and structure though because of this they find it extremely hard to handle even the slightest imbalance or deviation.
Yellow is the manifestation of Asgore's naivety though also his self-loathing. The times where Asgore is just blindly kind, maybe letting one get away with far more than they should. Even if it does hurt him in the long run, like constantly giving away his flowers for free. Also the times where Asgore is just, thinking about how his life is now and that he deserves it. Deserves to have no money, deserves his wife's anger, deserves to have his kids grow distant from him. That he deserves to just, suffer. This explaining Yellow having no self awareness when he's being tricked or lied to. Simply taking everything he's told at face value. Then beating himself up so much for failing to see it, usually wanting to punish himself in some way then even blaming himself for not doing that right.