Older male youner female lead romance

http://mydramalist.com/10516-the-spring-day-of-my-... The spring days of my life

im hoping to find a kdrama that the leads have at least 10yr age difference and more of a heartwarming and tearjerking drama just like this one ^ pls suggest me some heartwarming n tearjerking agegap kdramas thx

There is this fluffy Thai romance drama, Lovey Dovey (2016). It was based on a famous novel Lovey Brother and Dovey Sister. The other lead couple has an older guy and younger girl relationship. He was a twelfth grader (18 y/o maybe?) and she was just 10 years old when they first met years ago, wherein he was smitten by her cuteness and liked her instantly but he never came anywhere near her nor actively pursue her until she turned 18. In fact, he finished his studies in the US before coming back to Thailand. The other lead couple is the younger girl's  super protective, feisty older sister (she's the best friend of the older guy as well) and the older guy's younger brother (younger guy-older woman relationship).

Noona:

• I Hear Your Voice
• Ms. Perfect
• Madame Antoine
• I Need Romance 3
• Witch's Romance
• High School King of Savvy

Older Man (based on the ages of the actors):

• Marriage Contract - Lee Seo Jin is 17 years older than Uee
• Goblin - Gong Yoo is 12 years older than Kim Go Eun
• Bring It On Ghost - Ok Taec Yeon is 11 years older than Kim So Hyun
• Moon Lovers: Scarlet Heart Ryeo - Lee Joon Gi is 11 years older than IU
• Hi! School Love On - Nam Woo Hyun is 9 years older than Kim Sae Ron (she turned 14 while filming)
• Love in the Moonlight - Park Bo Gum is 6 years older than Kim Yoo Jung (she was 16 at the time)
• Doctors - Kim Rae Won is 9 years older than Park Shin Hye
• The Princess' Man - Park Shi Hoo is 8 years older than Chae Won
• Gu Family Book - Lee Seung Gi is 8 years older than Suzy
• Shopping King Louie - Seo In Guk is 8 years older than Nam Ji Hyun
• Kill Me, Heal Me- Ji Sung is 8 years older than Hwang Jung Eum
• Suspicious Partner - Ji Chang Wook is 8 years older than Nam Ji Hyun
• General and I* - Chung Wallace is 15 years older than Angela
• Imperial Doctress* - Huo Wallace is 8 years older than Liu Cecelia

*Chinese dramas

Older Man (based on the characters):

• Doctors
• Marriage Contract
• Suspicious Partner
• Because This is My First Life
• Moon Lovers: Scarlet Heart Ryeo

Older Man (the character is immortal):

• You Who Came from the Stars
• Goblin
• Hwayugi
• Gu Family Book