Answer:
You use a knife to slice my head and weep beside me when I am dead.
The faster you run the harder it is to catch me
My first is in riddle but not in little. My second is in think but not in brink. My third is in thyme but not in time. My fourth is in mother but not in brother. My last is in time but no t in climb.
When you stop and look you can always see me. If you try to touch you cannot feel me. I cannot move but as you near me I will move away from you.
I am a tool for fairies.
I am a animal that is cute but dangerous, what am I?