There is never an obligation to resign. By the rules, checkmate wins the game and every player has the right to make you prove that you can pull one off.
I've played on some occasions against one specific player in otb tournaments. He has the principle of playing every game out until mate. I do respect that behavior, it doesn't particularly bother me to have to play out an easily winning position. If anything, it trains my reflexes at it for faster time controls. Still, should you be bored, you can always try to find the quickest way to win as a challenge for yourself and boom - game gets interesting again.
If he's only rated 800 (so very beginner-level), I can understand it a lot more even. Back when I was only playing very occasionally, in one of the first games I won against my father, I got to a KQ vs K ending and he made me play it out. I had no experience about the correct approach and I really had to go through some trouble not to stalemate him. So, in that case, I find it a perfectly justified attempt for him to have played on. (Later on, when I got a bit better, he would resign earlier on). Conversely, good GMs resign all the time in endgame positions that I maybe couldn't convert at all, let alone easily. It only makes sense to resign, when *both* you and your opponent are good enough to understand how a position is completely lost. If he's an 800, he's naturally going to understand this a lot less than you. Plus, maybe he wants to learn by seeing how you're going to convert this or that position. In which case I'd find it disrespectful from you to wish to deny him this opportunity. When you're already winning, you really don't have much reason to complain.
The one thing that I admit is annoying is when a player just stops trying but still plays on, throwing out any unmotivated, bad moves (or, of course, the online behavior of letting your clock run down). Trying your best I can always respect, no matter how lost the position. Even so, I've signed up for a chess game and I don't think I'm entitled to anything more than my opponent abiding by the rules.
Long story short: no, you are never entitled to resignation by your opponent. On principle, it is always better to resign too late than too early.
(For funsies, you can have a look at this playlist -
m.youtube.com/playlist?list=PLeq1Gl9NLFoqJxwZNobe-RxRoaZXfRETv)