UNDERSTAGE: The Undertale Musical (act 1)
arielz83 for Monster Kid
Monster Kid (sometimes referred to in the show as Monty simply for some semblance of a proper name) is the youngest of the Snowdin trio. He sneaks out of his house to go see the Royal Guard in action, whom he's a fanatic for. He is likely Undyne (the leader of the guard)'s biggest fan, and follows the protagonists into Waterfall to be able to see her.
Y-yo, I'm here! Don't tell my parents I was here, I'm supposed to be doing my homework!
Did you see Undyne? Yo. She's AMAZING! She's always beating up the bad guys... man, I wanna be just like her when I'm older!
Hey, yo, check it out! This river’s super big! And hey, way downstream, I can see more stuff! Let’s cross! Wait… I think I see something coming downstream this way! It's a boat, that's soooo cooool!
(Singing examples in the character's voice, higher range)
Some direction for you! Could you try making his voice a little deeper and less feminine? I think it would work well.