Hey there. Someone already gave a very detailed explanation, so I hope you managed to get it. This scene can be missed if you are at the first firewall (after the Elecmon scene and then the drool scene that allows you the Clawjob) and then cum inside Gomamon in any way. You have to always pull out instead. Never inside, giving you the Blowjob option earlier and then screwing it up as well by cumming outside. It is a bit hidden in a way, but that is what makes it special. ^^