So, a couple friends and I actually came up with a theory about why Olivier hates Roy. It's just a bunch of crack, but I'll share it.
YoungRoy: *Runs into room shouting* You'll never defeat me!
YoungOlivier: *Is chasing Roy with a plastic sword in her hand* Give me back Fuhrer Sparkles!
YoungRoy: *Laughs and turns to face the blonde* What was his name? *Dangles the stuffed bear over the lit fireplace*
YoungOlivier: *Throws her sword at him and whines* Roy-ee, give him back!
YoungRoy: *Rubs the bump on his head while still holding the stuffed bear over the fire with his other hand* As long as you promise to stay out of our fort, it's boy's only!
YoungOlivier: *Lunges for Fuhrer Sparkles* No, let me have him back!
*While the two struggle over possession of the bear a loud rip is heard and both fly backwards.
YoungOlivier: *Stares at the body of Fuhrer Sparkles* Mo-om, he killed Fuhrer Sparkles.
YoungRoy: *Looks between the head of Fuhrer Sparkles and Olivier* Oops, I've gotta go. It's, uh, time for dinner. *Throws the head towards Olivier*
YoungOlivier: You'll pay for this Roy!!!
Then we went onto think up ways to save Fuhrer Sparkles from being decapitates, and after finding this picture
I wrote up a reason why he can't be saved. Horseman is Roy and Pipsqueak is Ed--their mission is to stop all wrongful decapitations. XD
Horseman is dismayed at seeing a child that looks not too dissimilar from his childhood self, and a blonde girl that doesn't look unlike one of their hero companions when she was a child fighting over a bear. Pipsqueak sees his companion's bewilderment and during the caped crusader's moment of hesitation walked up to the two children. The children cease their tugging, but still keep thier hands on the bear. The girl scowls and her eyes dart around the room until she sees her (idiotically) discarded wooden practice sword. Horseman rears to life. "Now children-"
He's cut off by the boy's shouts, "They're real, they're real. I told you Livvy." He sticks his tongue out at her. She sees the proper moment and tugs on the bear.
Horseman realizes their job is finished as the two children start arguing over who thought the two heroes were real. The two leave in a flash of blue light as Pipsqueak open the portal to take them back to their own time.
Horseman and Pipsqueak arrived in their present time to find the world a much different place. For starters the heroine, Blade Master, who had hated Horseman before he and Pipsqueak had stopped the decapitation, pounced on Horseman the minute she saw him. He was stunned into silence when she wrapped her arms around him, and attempted to kiss him. When he backed away in surprise she made her full lips form a pout. "Didn't you miss me?" she asked as her hand traveled to the hilt on her hip.
Horseman turned to Pipsqueak. "What have we done? Something must have gone amiss during our last mission. Where is Horsegirl?"
Pipsqueak shrugged his shoulders. "Should we go back?"
"Yes!" Horseman leapt away from Blade Master and joined Pipsqueak as he opened the time portal. Soon they were in the same room they had been in watching themselves stare at the two children fighting over the bear. Horseman suddenly remembered why the children seemed so familiar. "That's me," he told Pipsqueak.
"So you were a jerk back then, too?" Pipsqueak asked under his breath.
Horseman didn't respond to the comment, but yelled at his childhood self, "No, don't let her get the bear!" The two Horsemen stared at each other. The one with the knowledge of what it would change in the future gave himself a look that said, 'trust me, we have to let this decapitation happen.' Horseman's and Pipsqueak's past selves left, but the others stayed to make sure the universe went back to normal. As soon as Horseman heard the satisfying rip he gave Pipsqueak the signal to open the portal back to their time.
When they returned Horsegirl was waiting in their secret hideout to find out how their first "past mission" went. From the look on her companions faces she knew something had gone severely wrong. "Didn't I say that was a bad idea?" she asked while she polished her guns.