I have wondered such things too. And, yes, you'd hope there were very little breaks and that was by her choice. This is why I want to see someone have a big clock in a scene- to show that there were no breaks in the action and the girl literally swallowed cum for x amount of time. To me, this would be much more impressive and a much better barometer for who the real cum swallowing queen is.
Let's say for a 30 minute period maybe- how many loads could Miki S, Megumi S, Hana K, Maki H, Mika O, etc, swallow if all were given the exact same time frame and same number of guys? Fascinating to ponder lol...
I have to have hope that gokkun will return to its glory days again some day. It's depressing to think otherwise lol.
I think there was an American movie called something like Suck Off Races, and it featured this really cute Chinese girl (Kita Zen) who blows 15 guys in a row (They all cum on her), the objective being to do it faster than the other girl. Very hot stuff! Did not mean to stray into non JAV, but your comment made me think of that.
Also to your point, I LOVE titles such as the following, which trend pretty close to what you are suggesting:
GS-001 starring Shion Fujimoto. I believe she was 21 years old when they filmed this movie, but in the first scene 30 dudes line up and she sucks them off one by one. It is unbelievably hot and she keeps having to change position because her legs are obviously bothering her after just a few guys. Then she fucks a few others just because...
Then we have Rin Hifumi in both SDMU-840 and SDMU-854. In 840 she blows at least 10 guys in a row in one scene and absolutely loves it. This apparently was not enough for her, so in 854 she blew 33 guys in a row and they all came all over her face. 854 is an insanely hot piece of work. She cannot stop sucking dick and even at the end of the scene, covered in cum, she looks ready to suck off the production team as soon as they cut.
What is especially great about Rin, is that 840 and 854 are her second and third titles, respectively. Apparently, Rin the country bumpkin saw porn, wanted to be in porn because she craves dick soo much, that she called to try and break into the industry. Not sure how she actually got cast, but it is funny to think this country girl showed up and starts talking to these producers like, "I want to suck as many dicks as you can put in front of me, and I will fuck too so don't forget about that". Having heard that line before and setting her up with the crew in 840, they probably were thinking she was gonna tap out after 5 loads to her face, only to have her finish the scene like, "Where are the others?".
Can just picture the story she gave her parents, "Mom don't worry, I am just going back to Tokyo to see some friends", leaving out the part where she is going to a random building where 33 guys (Old and young) are waiting for her to show up and suck their dicks so they can drop their loads on her face. "How are your friends doing?" Her mom probably asked when she showed up later that night. LOL.
https://news.dmm.co.jp/article/1059249/
https://news.dmm.co.jp/article/1062968/
There are others somewhat similar, like NHDT-465 with Maka Mizuno, where she fucks and sucks 51 guys (I bought that one because someone else on this forum brought it up, what a score!), I like the above titles soo very much, especially GS-001 and SDMU-854 soo much because of the overall continuity, as in they start shooting and go pretty straight through to the end of the scenes. The MIAE titles were solid as well, especially the one with Aya Miyazaki, I mean, they FUCKED HER UP!!
Granted I still like the XRW, Pacifier Prep and ASW series as those scenes are pretty certainly filmed one after the other, so by the final scenes those girls have swallowed a lot of cum in one day and some of them really show it, lol.
Overall, my favorite dynamic is when they have to suck one guy after another, in the same scene, until everyone goes home satisfied.
KV-212 is a solid example as well and it would be awesome to see more like that!
Recently I've gone back and watched a lot of older titles and I stumbled across one that for whatever reason I hadn't watched in a long time. It's the one with Miki Uehara (Cum-Gulping Toys), sorry I can't find the exact number, but everyone should go back and check it out.
The last scene is absolutely fantastic. She's got an amazing body first of all, and just the most amazing dick sucking pouty lips you'd ever want to see. In the last scene she gets fucked mercilessly, and when guys start cumming into her mouth, she does what I love in this genre the best- she swallows immediately, as if she loves cum so much that she can't wait to swallow it the second she has a chance.
The only issue is that the mosaic is heavy at times. But another thing I like about the scene is there's a lot of guys just cumming on her face too and it's easy to see this drives her wild and soon she starts scooping every bit of cum into her mouth she can. There's not been scenes like this in forever. When guys are cumming in rapid succession, one after another. She takes it all and seems to get more and more turned on with each load. I wonder why she did so few gokkun titles, she was amazing in this title.
Miki is such a fucking slut, I love it. Everything I have ever seen her in she practically begs for dick. When she is getting gangbanged she cums super hard and when she gets facialed or swallows cum you would think she is at the spa. What a performer!! Seems like she jumped into the industry, did a slew of work in a short period of time, and then disappeared. Shooting star to say the least!