Climb the ladder.
Return to L33tz4n.
Relose Chaos Grape.
Don't choke.
Push Chaos Grape further into mouth.
Go back to the rift.
Stick LSOD into the ground, basket end up.
Lean basket end far back, so it's on the opposite side of the LSOD from the rift.
Hold backet end down with Bookmark of Eternity.
Hold onto basket end.
Grab Bookmark of Eternity.
Let go of LSOD just before it finishes springing up.