I have a few, though most are on TH instead of Spotify or Youtube!
Bastian: Solitude, death, and 'just a guy' vibes
Lance: Upbeat and nostalgic but with some insecurity undertones
Eva: Logical and medical-themed with some sinister vibes and an elegant instrumental as a treat
Flax: Death, memory issues, lack of autonomy, and feeling like a monster
Wasp: Depression, repressed anger, and the feeling of inadequacy
Nyx: Science and some playful villainy (I haven't sorted it yet though so the vibes are probably a mess rn)