It looks like the orientation is just changing instead of the position, if you always want something to be behind all the time maybe look at this topic:
I’m not too sure what you want, but I think you want this -
Part behind.wmv (1.2 MB)
So this is the script
-- put this serverScript into game.StarterPlayer.StarterCharacterScripts
local tweenService = game:GetService("TweenService")
local part = game.Workspace.Part
local character = script.Parent
local humanoidRootPart = character:WaitForChild("HumanoidRootPart")
local moveBehindTween
local prevHumanoidRootPartPos = humanoidRootPart.Position
local timeToReachDest
local easingStyle = Enum…