5. Eternal Love(only the ML wasn't born yet/was super young)

7-My Fated Boy : the promise was made and never actually rescinded even though everybody but the boy acted like it was a forgone deal. 

8- Moonshine and Valentine

10. Sweet 18 

next person please choose a new topic

10 k/cdramas where the leads don't drink

Isn't Sweet 18 the same drama as My Little Bride (#6)? 

 hayaka:

Isn't Sweet 18 the same drama as My Little Bride (#6)? 

No, but I also thought the same

 hayaka:
Do they have to be adults?

yes

 I AM SHOOKETH:

yes

Well, the ML in Reset is 25 or so, so I guess that counts.

3. Doctor Romantic 2 - It's been so long since I saw this drama but I dont remember the leads drinking.

4. color rush 

5. dream high

6. given

 Wander:

4. color rush 

5. dream high

6. given

Aren't these all of high schoolers? The topic poster asked for adults, and one is a Jdrama.