Episode Overview

Home Alone Episode 644 delivers a perfect mix of raw emotion and lighthearted solo-living vibes. The episode features two main stories:

• Part 1: Ku Sung-hwan (구성환) and Hongga’s dramatic final day of their 446km cross-country walk from Seoul to Gwangalli Beach, Busan.
• Part 2: Actor Yu Su-bin (유수빈) as the Rainbow Friend, showcasing his lazy-yet-disciplined daily life and heartwarming outing with IU and Lee Yeon.

1. Ku Sung-hwan & Hongga: The Final 25km to Gwangalli Beach 🚶‍♂️🌧️

Key Moments

• After 16 nights and 17 days, only 25km remain on the last day.
• They battle heavy rain, strong wind, hail, and endless stairs/mountains.
• Sung-hwan pushes through severe pain: blisters, limping, stiff calves, back pain, and near-hypothermia.
• A kind fan recognizes actor Ku and gifts him warm coffee — a touching moment that gives them strength.
• Spontaneous barbershop visit for a mindset reset: Sung-hwan goes for an extreme 1mm buzz cut (monk-style), Hongga gets a stylish cut and shaves his 10-year beard.
• They rely on each other heavily — “You can’t do this alone.”

Reflections in the Studio

Sung-hwan shares how the journey helped him overcome a failed attempt in his 20s, combat negative self-talk, and find strength to keep going one step at a time. The cast praises their incredible willpower.

2. Yu Su-bin (유수빈): The Leather Jacket Freak & Infinite Challenge Obsessed Solo Lifer 😎📺

Daily Routine Highlights

• Wakes up and immediately does a high-incline treadmill workout while watching Infinite Challenge (his ultimate comfort show — watches episodes repeatedly).
• Quirky healthy habits: drip coffee, blueberries for immunity, peanut butter, apple/watermelon cutters, supplements placed within arm’s reach.
• Extreme laziness mixed with discipline — everything (tablet, massage pillow, eye mask) stays on or near the bed.

Heartwarming Outing with IU & Lee Yeon

• Cherry blossom walk along the Han River (Su-bin tricks the homebody IU into exercising).
• Delicious Chinese restaurant meal: signature fried blowfish with chives, tangsuyuk, and movie quote quizzes.
• Photo booth fun and genuine friendship moments.
• Su-bin shows his caring “older brother” energy while needing alone time to recharge afterward (beer + tuna bread solo time).

Overall Episode Themes

• Perseverance & Mental Strength: Pushing through pain (physical and emotional) one step at a time.
• Pet Loss & Grief: Beautiful, honest discussion about processing the loss of beloved pets.
• Friendship & Support: Leaning on friends during tough times and the joy of shared memories.
• Solo Living Realities: The balance between loving independence and needing human connection.

Memorable Quotes & Scenes

"You can't do this alone. They got each other." — Studio reaction to Sung-hwan & Hongga

"I kept my promise to Kkotbun." — Sung-hwan at Gwangalli Beach

"Infinite Challenge is the best show to me." — Yu Su-bin

"Hard times are more memorable." — Sung-hwan staying positive in the rain