Question: Who is the star character of the film which "Spring Day" was loosely adapted from?

Context articles: Spring Day (painting)
One Fine Spring Day
Spring Day
The Athlete (1932 film)
The White Haired Witch of Lunar Kingdom
Spring Day (TV series)
Yoo Ji-tae
Hoshi no Kinka
Wings (BTS album)
Curtis Wilkins

Spring Day is a painting by the well-known Russian artist Nikolai Matveevich Pozdneev (1930–1978).
 It attempts to convey the mood of Soviet society of the late 1950s to the early 1960s.
One Fine Spring Day is a South Korean feature film released by Sidus and Applause Films in 2001.
 Directed by Hur Jin-ho (of "Christmas in August"), the film is a portrait of a love affair - from its blossoming in spring, to its decline as the years pass.
Spring Day is a holiday marking the coming of the spring season, which takes place in different countries, on varying dates.
The Athlete is a 1932 short animated film by Walter Lantz Productions, and distributed by Universal Pictures.
 The film is the first of a film series featuring Pooch the Pup, the first star character created by Walter Lantz.
The White Haired Witch of Lunar Kingdom is a Chinese wuxia-fantasy 3D film loosely adapted from Liang Yusheng's novel "Baifa Monü Zhuan".
 Directed by Jacob Cheung and produced by Bona Film Group, the film stars Fan Bingbing as the title character, with Huang Xiaoming, Vincent Zhao and others among the supporting cast.
 Originally scheduled for release on 25 April 2014, the film was moved to 1 August 2014, then moved a day earlier to 31 July 2014.
Spring Day () is a 2005 South Korean television drama series starring Go Hyun-jung, Jo In-sung, and Ji Jin-hee.
 Loosely adapted from the 1995 Japanese drama "Heaven's Coins" (星の金貨 , Hoshi no Kinka ) , it aired on SBS from January 8 to March 13, 2005 on Saturdays and Sundays at 21:45 for 20 episodes.
Yoo Ji-tae (born April 13, 1976) is a South Korean actor, film director and screenwriter.
 After a stint as a fashion model, Yoo launched his acting career in 1998 then rose to fame through the films "Attack the Gas Station" (1999) and "Ditto" (2000).
 In the succeeding years, he gained acting recognition by working with acclaimed directors such as Hur Jin-ho in "One Fine Spring Day" (2001), Park Chan-wook in "Oldboy" (2003), and Hong Sang-soo in "Woman is the Future of Man" (2004).
 Yoo began directing short films in 2003, which were well received in the film festival circuit.
 His feature directorial debut "Mai Ratima" was released in 2013.
Hoshi no Kinka －Die Sterntaler－ (星の金貨 , "Stars' Coins") is a 1995 Japanese television drama series.
 The series revolves around Aya Kuramoto (倉本 彩 , "Kuramoto Aya" ) , a deaf and mute girl from Hokkaido who is in love with a doctor named Shūichi Nagai (永井 秀一 , "Nagai Shūichi" ) .
 After Shūichi leaves for Tokyo, he has an accident and loses his memory.
 Aya travels to Tokyo and encounters Takumi Nagai (永井 拓巳 , "Nagai Takumi" ) , Shūichi's brother.
Wings is the fourth studio album by South Korean boy band, BTS.
 The album was released on October 10, 2016 and also available in four versions of physical album.
 It contains fifteen tracks with "Blood Sweat & Tears" as the lead single and seven solo tracks by each member of BTS.
 The album is heavily influenced by Hermann Hesse's bildungsroman, "Demian".
 The album was reissued under the title You Never Walk Alone and was released on February 13, 2017 as an extension of the standard release.
 The reissue album is also available in two versions of physical album.
 It contains eighteen tracks in total including four new tracks with "Spring Day" and "Not Today" as the lead singles.
 Overall, sales from both albums has exceeded 1.5 million physical copies worldwide with one million copies sold in Korea, officially earning BTS the title, 'Million Sellers'.
Curtis Wilkins is star character of the comic strip "Curtis" created by Ray Billingsley.