There are only a handful of spells with a duration of concentration.
While these spells are active, can the caster be subject to a Targeted version of Dispel Magic that does not aim at a spell, but rather the creature (presumably with the intention of ending all spells on that creature). Ostensibly, is the Concentration spell considered to be 'on' the caster?
For example, the Implosion spell has a duration of Concentration, which suggests that the caster is actively maintaining a magical effect (which they're using to smush others into goo). Given that others may be averse to being smushed into goo, could another character target the caster of Implosion with Dispel Magic to end that spell along with any other beneficial spells that the caster may've set up?