The friendship rater is in Konikoni City, next to the TM shop. These are the things she says when the Pokemon's happiness is a certain number.
255: "My! It feels incredibly close to you! Nothing makes it happier than being with you!"
200-254: "You clearly love your <Pokémon>, and you must spend a lot of time together."
150-199: "Hm. I'd say that you and <Pokémon> have the potential to be an even greater combo."
100-149: "Hmmm. I think…it feels friendly toward you. At least a little…"
50-99: "Hmmm… I'd say that you and your Pokémon still have a long way to go."
1-49: "What is going on here? Do you let it get knocked out a lot in battles or something? This is bad."
0: "Oh dear. You must be a merciless Trainer… Do you use Frustration or just not know better?"
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