It's a fantasy role-playing game.

DM: You are Taryon Darrington, a human artificer . You are the member of the famous group of adventurers. Previously, The damage quickly reverts them out of their eel forms. The fight comes down to simply destroying as many of the tentacles as they can, hoping this will allow them to get away.
DM: As you draw its life force away, grabbing onto the tendrils of its tentacles like, "Argh!" You watch as the necrotic energy pulses into it and pulls the life force into you
Player: Okay.
DM: All righty.
Player: Y'know, small but okay.
DM: All right.
Player: And once again casting, recasting Sanctuary on myself.
DM: All righty.
Player: Because it went away when I did that.
DM: Sanctuary is concentration?
Player: No, well, I don't know, but it goes away when I attack him.
DM: True. However, if Sanctuary is a concentration, 'cause Vampiric Touch is also a concentration.
Player: Well, it would have gone away either way, right?
DM: I'm saying, if Sanctuary is a concentration spell--
