This plugin adds simple commands for player-to-player direct messaging, creating / editing group chats, and quickly responding to messages.

DM's
send message:
/msg <player> <message>
/dm <player> <message>

GROUPS
create group:
/group <group name> add <list of players>

edit group:
/group <group name> [add | remove] <list of players>

chat to group:
/msg <group name> <message>
/dm <group name> <message>

list group members:
Hover over group chat name in send or respond chat notification

OTHER
respond to message (direct or group):
/r <message>