+-------------+     +------------+     +------------------------+
| MemberEvent | --> |   Event    | --> |       EventGroup       | <-----+
+-------------+     +------------+     +------------------------+       |
  |                                      ^                              |
  +-------------------+             +----+                              |
                      v             |                                   |
+-------------+     +------------+  |  +------------------------+     +------------------+
| MemberRole  | --> |            | <+- |   MemberEventOption    | --> |   EventOption    |
+-------------+     |            |  |  +------------------------+     +------------------+
  |                 |            |  |
  |                 |   Member   |  +-----------------------------------+
  v                 |            |                                      |
+-------------+     |            |     +------------------------+     +------------------+
|    Role     |     |            | <-- | MemberEventGroupOption | --> | EventGroupOption |
+-------------+     +------------+     +------------------------+     +------------------+
                      ^
                      |
                      |
                    +------------+
                    | MemberJoin |
                    +------------+