Wah! I can relate somewhat,but unfortunately I don't have manga
1. Kill / murder those who disagree that DC is the best!
2. Talk DC all the time with friends and classmate
3. Spread DC love
4. Collect everything that has conan face/ any conan stuff even you're out of money,you'll barrow from your parents just to buy those stuff
5. My profile in FB is a DC chara and I have DC avatar! XD
6. Sing DC song
7. Rewatch hundred times of DC ep
8. Friends with DC fans...
9. Draw Conan everywhere
10. Make conan an inspiration in school. If there's a homework,sometimes I base on Conan lessons
11. Mobile full of conan stuff
12. Download amv's
but I know my twin is more obsess than me,ohohoho~!