How old was each hero at the end of the novel in which he is the main character? Let's compile a list and see who is oldest/youngest.
LOCH - 20S
ROCH - late 30s
HSDS - 20s
DGSD: Xiao Feng - early 30s
DGSD: Duan Yu - 20s
DGSD: Xu Zhu - 20s?
SMILING PROUD WANDERER - about 30
ODE TO GALLANTRY - late teens?
SWORD STAINED WITH ROYAL BLOOD - no clue
OUTER STORY OF FLYING FOX - no clue
BOOK & SWORD - no clue
DUKE OF MT DEER - 17 to 20-ish
YUE MAIDEN SWORD
LINKED CITY
TWIN SWORDS
White Horse Neighing in the West Wind