OMG, SO MUCH KOYUKKURI TALK! I gave up and just did the s-to-sh conversion.
1. Reimyu ish a Marisha! Reimyu hash a mishter gold badge! Reimyu ish a pet yukkuri! Give her shweet-shweets, okay? Footshiesh are shore, sho carry Reimyu, okay?
2. "Marisa... My pet yukkuri Marisa disappeared around here. Have you seen her?"
Reimyu'sh not a Marisha!! Are you shtupid? Die! Bring shweet-shweetsh to apologize, okay?
"...but you're a pet yukkuri, aren't you?"
Reimyu ish a Marisha! She'sh a gold! Take her home now, okay?
3. "Oh... so you're a gold-badge Marisa, right?"
Not a Marisha! Take a good look at Reimyu'sh beautiful mishter ribbon, shtupid!
"Then take off your pointy hat. If you're a Reimu, I can't see your ribbon, you know."
Mishter hat hiding Reimyu'sh mishter ribbon, die eajy!!!!
YUPIIIIII!!! Reimyu ish a gold pet yukkuri Marisha!!!
"But you don't have a badge and you're wearing a ribbon. And you just said you were a Reimu."
Re-Re-Re-Reimyu just dropped her mishter badge! Oh, there'sh mishter badge! She'll put it on eajy!
"Huh? What, that hat is yours? That seems about right... there's no way a scummy Reimu could be a pet yukkuri, is there?"
Reimyu ishn't shcum! Apologize now!
"So you're a Reimu, aren't you? How come you're wearing a hat? Are you a Marisa? Are you a Reimu? If you're wearing a hat, you're not a scummy Reimu. You're a pet Marisa, so I won't kill you."
5. "Anyway, Marisa, do you know what happened to my Marisa?"
Reimyu ish... Reimyu... ish...n't a Reimyu, she'sh a Ma-Marisha.
"I know, Marisa. You're wearing a hat, so you're a Marisa. You don't look like a scummy piece-of-shit Reimu, Marisa. Marisas are mostly good, aren't they, Marisa?"
Re-.....Marisha...ish a Marisha...
"No, it's okay, Marisa-who-isn't-a-Reimu."
That'sh right! A Marisha! Reimyu ish the Marisha Mishter ish looking for! Reimyu forgot to mention it, shorry!!!
"..."
6. "I slipped up, too. You are wearing the badge of the baby Marisa I'm looking for, aren't you?"
That'sh right! Don't leave Reimyu alone, okay? Humansh have to give Reimyu shweet-shweets! Hurry up and bring them, okay?
"You know, I really, really hate Reimus. In my current mental condition, the moment I see one, I might tear it apart and kill it. ... By the way, weren't you looking a little Reimu-ish a little while ago?"
Reimyu ish a Marisha! Don't take it eajy, undershtand it, okay?
"I'll just clean your hat off a bit."
What are you doing!? Reimyu'sh mishter baaaadge!!
"Huh? Under your hat, there's a dirty red ribbon... It must've gotten caught on you somewhere. I'll take it off."