Yamamoto dun goofed when he tried to trigger the Yui flag in his once-in-a-lifetime character event.
I mean, choosing the passive "I want to protect
you" option? Without the stats to back up the talk?
That's an automatic BAD END there.
At least he died with some degree of dignity, having unlocked the module, earning Yui's respect and bullet-to-the head.
And that he didn't have to watch Yuuya triggering flags like a boss.