The way to know someone is to meander through their memories. Hence, if there's a Marauder's Map in Harry Potter, Seulgi has a "map of memories," of experiences that meant a lot to Joohyun. This is where Taeyeon became quite helpful, as she shared what she knew about Joohyun to Seulgi. 

The map of memories led Seulgi to take Joohyun again to the following and revisit, re-create, her memories of:

a. failing to learn how to ride a bike at Circle

Joohyun was pleasantly surprised when she found out where Seulgi took her one Saturday morning. As she scanned the Circle park in Quezon city, she felt like she was that 7 year-old kid again who scraped her knee as she tried - but failed - to learn a bike. 

"Dun, dun sa spot na 'yun, ilang beses ako sumemplang," Joohyun laughed as she slurped her taho. 

"Subok ka ulit ngayon, Hyun," Seulgi told her. "Tuturuan kita."

"Pero kung gusto mo lang," she said, reassuring her, as she took out something from her huge backpack. 

Joohyun's eyes crinkled at the corners as she saw what Seulgi was holding. 

It was a helmet, with Seulgi's doodles on it. There was a drawing of a happy Joohyun, of rainbows, of words that say - kaya mo 'yan Hyun!

"Kung hindi mo naman gusto, ayos lang din, puwede mo pa rin naman suotin 'to tapos maglakad-lakad na lang tayo," Seulgi said. "I'd wear mine too," she told her, getting her own helmet from her bag. 

Joohyun beamed at her. That day, she learned to ride a bike.

b. finding the Aling Tindera of the best Japanese corn in Katipunan

Taeyeon told Seulgi of how Joohyun asked her to sneak out with her during summer just so they can buy, in her words, "the best Japanese corn in Katipunan." They will walk almost the whole lane passing through Ateneo to Miriam, searching through the array of sidewalk vendors selling Japanese corn to find Jooh