It's more about what you eat and when you eat.
It's about knowing your body.
If you eat stuff that makes you poo "solid" and you know when to eat, you won't have any problem, just when you go to the loo do it all, then don't eat anything till the sex date is over, this way I stayed clean with a black 11" cock pumping my ass for FOUR hours pretty recently (unbelievable).
This is the best way to be clean and it really works.
If instead you have eaten stuff that make your poo soft and your digestion is not finished, regardless the length of the cock, expect stuff coming.
As long as you need to go to the loo once during the intercourse I think it's not a problem, the problem is when the stuff keeps coming all the time.
Never do an enema, that's absolutely not hygienic and should be done only by a nurse with the proper tools and knowledge and for a very good reason.
If you do an enema you will go on shitting brown water for hours and that's not really what you want to happen when you're in bed with you horse hung fella.
Another solution is the anal douche that is not an enema, I recently bought one, it looks like an enema BUT IT'S NOT, you just pass water in your ass, the water just enters and exits immediately and while doing this it cleans up.
You must sterilize it between each use.
I strongly suggest not to use the plugs for the shower, it's definitely not hygienic and it's pretty dangerous, I just think to some places where I've been that when you turn the shower you get cold water, then immediately a rush of 100 degrees celsius water, it's up to you if you want to have 1st degree burns in your ass.
Don't even think to use a douche found in a public place unless you are looking to catch some infection or STD, it looks obvious that you wouldn't do it but people still do it, for instance I've been for a while in Australia and I've discovered in gay saunas now have to provide "disposable" douches, you don't find the fixed one anymore.
...and I am really scared that it took a LAW to achieve this, it's just... shocking.
Be aware that enemas and douches make the skin within your arse more absorbent so if the condom breaks it's more likely than usual that you would get infected i.e. by HIV.
If you do an enema or an anal douche, and your digestion is not finished yet, and you have eaten something that makes your poo soft, you should expect some stuff coming anyway.
P.S.: I LOVE tops who get fucked only sometimes, that's really my favourite type of partner if I have to be the top one! especially when they're much much taller than me, broad shoulders, tight hips, masculine, tight ass and big cock!