Aishii, that's because people saw u with u're bleached hair and when it goes back to it's original color it will be noticeable till u bleach it again. Jolen and Andrea (for the face) are safe to use on the face.
Bleach doesn't make the hair thicker, if u don't thread the sides of u're face and opt for bleaching it will give u the "furry-face"!
Before trying out anything new on u're face PLEASE try a small patch on u're inner arm and check for reactions.
Before bleaching apply baby lotion to u're face, bleach doesn't burn and itch as much and doesn't affect u're skin and acts on just the hair. Creams that are steroid based can cause hair to grow back faster and thicker but regular bleaching creams are a mixture of hydrogen peroxide and a base cream. Hydrogen peroxide strips the melanin (pigment) from the hair and doesn't interfere with the growth etc.