Well I called bianca and she said, "You and Riolu... You seem really close! You look so, so happy! It's enough to make me happy, too!" what is my happiness level and how much more do I need to evolve my riolu? I bet serebii has a chart or something
The chart for Bianca's happiness rating is currently unknown. Instead, go to the Pokemon Fan Club in Icirrus City (The house with the dancing kids out front).
Show the Chairman your Riolu. Then match the phrase he says to the chart below. Riolu must have a happiness rating of 220+.
>"You two sure get along great! It looks like you are having fun being together! You seem bright and cheerful!"
Thats what Bianca will say when you are close to the level.
Source