Oooh. Self reflection? Are you going to start studying really hard, or something like that? [Said as if you're genuinely curious about what your friend means]

... Aren't you just gonna play games back at home, though... [Kind of sarcastically asking it, because he knows what Cheryl said was an excuse]

Y-your voice's probably fine. It sounds like no-leaf clover's voice, after all. [Awkwardly laughing it off]