[quote=@Noxx]
There's something I've been meaning to ask. Can Magical girls....feel each other like can they sense the residual magic flowing around one
[/quote]

Yes, though it’s more starking on opposing sides. Dark Magical Girls can sniff out the stench of purity from their light counterparts. Likewise, ordinary Magical Girls can easily pick up on their dark counterparts’ negativity. Hence Mari and the Detention Club easily sensed each other.