They aren't against the entire government nor the government system, merely against one person. While if an event happens to give reason for a ruler to be removed, it is much easier to convince people to protest him out instead of doing a rebellion.
The Ruler is the Government.
The thing is, that it IS impossible to remove a Royal from a realm. There is no way to actually remove them from your realm. The only current method that can even be attempted on them is Exile, but why should that noble leave. As Anaris stated earlier, leaving is stupid because Prestige and honor really don't mean anything in this game. A Royal cannot be removed from a realm under any circumstances.
Have you considered simply putting him on ignore, and forbidding everyone in the realm from speaking his name or addressing him? Fine anyone who supports him or acknowledges his existence.
Really? You're not creative (or mean) enough. Two options off the top of my head, I think they may have been mentioned earlier in the thread.
1. Have the lord of his region switch realms. This works best if you can pay them off with a better region on their return.
2. Give away their region. They'll still be in the realm, but they won't have any income. If he's a duke, have his lords switch lieges and then disband his duchy.
3. Put a 1000 gold bounty on his head, and then announce to all infiltrators that any infiltrator caught assassinating him will be released immediately with no repercussions. Notify him that you have done this. Repeat until he leaves the continent.
4. Get together with your ally (or possibly, enemy), and have them declare war on your realm (or you on them, whatever). Continually provide that realm with the location of the royal, so their army can harass him. If he has a region, have them loot it until it rebels. Use your own priests and diplomats to help the region revolt, and have surrounding lords drop their tax rates in order to make his peasants even more unhappy. Refuse to sell him food (or buy his food, depending).
If you're not willing to take these measures, then you don't deserve to get rid of him.
