Luna, Amber and Victoria, her former bandmates in girl group f(x), were among family members and close friends who attended Sulli's private funeral on Thursday (Oct 17).
According to the koreaboo portal, Amber came back from the United States while Victoria halted filming in China to support Sulli's family in their time of need.
Fans of the actress-singer, 25, who was found dead at home on Monday, had earlier paid their respects at another venue over two days.
The police have said that it will take a few days for a full investigation into Sulli's death to be completed, with an autopsy ruling out foul play.
The police will close the case if drug and toxicology results - which are pending - do not raise any red flags.
The authorities had earlier said there were no signs of a break-in at Sulli's home on Monday.
No will was discovered but a notepad filled with her thoughts about her life was found.
Her death has unleashed a debate in South Korea over the stresses faced by celebrities.
Sulli, who took a break from show business in 2014, reportedly asked her agency to go after netizens who posted spiteful comments.
She was targeted after rumours surfaced that she was dating hip-hop group Dynamic Duo's Choiza in 2013.
But even as other celebrities have enlisted lawyers to try to curb the problem, the malicious commenters have been hard to track down.
South Korean MPs are now said to be mulling over new rules to address the toxic culture which caused Shinee member Jonghyun to commit suicide in 2017.
Many people have petitioned the government to make it compulsory for netizens to use their real names online.
For some fans, the new call for greater action against abusers has come too late.
"When Sulli was alive, everyone bombarded her with malicious comments. Now that she's gone, all the comments are supportive. The world is a scary place," one person wrote.
Another posted: "I always rooted for you in my heart but I should have come out loudly and spoken for you."
The grieving has also made fans turn to a 2012 song, called Peach, for closure.
It is by Korean singer IU who said previously that she wrote the song for Sulli, a close pal.
The ballad is now back on the charts.