It's true; the thing to remember about Takagi is that she isn't remotely incapable of embarrassment or making mistakes, she's just got an incredibly good poker face and is good about making sure no one is around when she loses it.
This kid probably hasn't developed quite as good of self-control as her yet. Yet. By the time Chi is a middle-schooler this kid is going to have had years to work on that and he'll have had years to learn how she thinks.