Tri(ring)nity

  But there's apparently stg I can't see, I can't even imagine it, then translate it to the drawing is impossible.

I hate the obliquity of this ring!

 N°3 Graphite HB 2

 N°2 Graphite HB 2

N°1 Graphite and Cretatolor NERO extrasoft

Uff, 25 drawings in 25days!!!