The Gargantuan-Gazelle-Glare is when you catch someone off guard with a mix of surprise and mild annoyance. It’s like seeing a gazelle stop dead in its tracks, head tilted, one eyebrow raised in that ‘I saw that coming, and I didn’t like it’ way. Use it when someone does something obvious but irritating, and you want to say ‘I’m not mad, I’m just... mildly unimpressed.’