I use Dinto's Blur Finish Lip Tint to fill in my lip color. I am satisfied because it stains well and has good staying power. It finishes softly with a matte look, so there is no stickiness.
CommentsI’d like to recommend Hince Raw Glow Gel Tint 04 Fever.
It feels like a bright red mixed with a drop of pink, so it isn't too purple. It applies clearly, making it pretty for daily wear for cool summer skin tones.
The shine is like glass, but it isn't too sticky, so I think it would be fine to wear at school.
If you want something a bit more pink, I also recommend Daisique Juicy Dewy Tint 03 Pink Guava.
It has the clear and radiant pink characteristic of cool summer skin tones, so it doesn't make your face look dull. It has a moist, juicy glow, so I think it will match the vibe you are looking for.