Every Thursday, Asgar Brohi and his three daughters would visit a Sufi shrine in Sehwan to pay tribute to Lal Shahbaz Qalandar, one of Pakistan's most revered saints.

Just like many others, the labourer and his family members would head there to take part in a weekly dhamaal - a Sufi dance sending devotees into a state of trance.

But this Thursday, Brohi went to the shrine alone.

Last week, when Brohi stopped at the gate to speak to one of his friends, he asked his daughters to walk inside. He told them that he would join them at the shrine soon.

A minute later, he heard a huge blast.

A suicide bomber struck the Qalandar shrine, in an ISIL-claimed attack that killed more than 80 people.

Among the dead were Brohi's three daughters and two other family members, including the five-month-old son of his eldest daughter, Tehmina.

"The suicide attacker blew his explosives when everyone gathered at the tomb of Qalandar after the Dhamaal so he could kill the maximum number of people," Brohi told Al Jazeera.

READ MORE: Lal Shahbaz Qalandar and Pakistan's pluralistic history

"I immediately ran to search for my family. I saw dead bodies, some without their heads, others without their arms and legs," he said in a weak voice.

"The images still float in my mind; they don't allow me to sleep at night."

'I will still come here'

Syed Muhammad Usman Marwandi, better known as Lal Shahbaz Qalandar, is a venerated 13th-century Sufi philosopher and poet who taught peace and love and is respected across South Asia.

Legend has it that he was sent a bowl of milk filled to the brim by Sehwan's ruler at the time, indicating that there was no room for any more people and that he could not seek refuge there.

But Qalandar returned the bowl with a flower floating on the top, expressing his desire to be among Sehwan's residents and spread the fragrance of love.

His shrine has long been seen as a space where men and women from all classes, backgrounds and religions, irrespective of gender, can come together as one.

READ MORE: Sufis return to Sehwan shrine in defiance of ISIL

On Thursday evening, a week after the deadly attack, prominent Shia leaders in Lahore organised a special gathering at a shrine to honour the victims of the attack.

Leaders from Karachi, Quetta, Hyderabad and Larkana, as well as people from across Pakistan attended the emotional event.

With their heads down and eyes closed, hundreds swung their bodies back and forth to the drums' beats.

"I will still come here, every week," Brohi said.

"My daughters were killed at a pious place, and they are martyrs," he continued, adding that he wanted to spread the "message of love".

"This is our place where no one can judge us and we are united. Sufis will prevail."

The shrine is also known as Lal (red) after Qalandar's usual red attire.

Sharafat Ali still has the red thread he bought last Thursday at the shrine from a young boy selling it for as little as 15 cents.

The old tradition of tying threads to marbled mesh on the shrine's walls is believed to have powers to get a specific wish granted.

"I don't have children, I went there to request for a child. Many people told me that no matter what we ask for, the wish will be granted," Ali told Al Jazeera.

He also bought a body-length garland that many lay on Qalandar''s tomb.

Ali survived the attack, even after he was stepped on during a stampede.

"I've hurt my leg and I have a few scars on my head, but I survived and have been discharged from the hospital," he said.

"It was my luck, I could have been dead now."

Cursing the suicide bomber, Ali said the attacker could have been stopped from entering the shrine and the deaths could had been averted if there was enough security.

But without hesitation, Ali said he will go back when he recovers to tie the thread "to where it belongs".

'Love can conquer all'

ISIL, also known as the Islamic State of Iraq and the Levant, claimed responsibility for the attack as they oppose the culture of grave worshipping, arguing that this may lead to the worship of anyone other than God.

Other armed groups, such as the Pakistani Taliban, have also frequently targeted shrines for not conforming to their strict, literalistic interpretation of Islam.

But worshippers believe that they stand by the values of harmony, tolerance and love.

In a show of determination one day after the attack, civil society representatives staged a protest walk which concluded with a performance by classical dancer and social activist Sheema Kermani.

Walking towards the shrine was very emotional, Kermani said. A feeling of "great sadness" overcame many participants, with some in tears.

"But then the Sufis who were with us started reciting verses praising Qalandar Shahbaz and we started doing the dhamaal; the shopkeepers started throwing flower petals on us, so an atmosphere and energy of life infused among all of us," Kermani told Al Jazeera.

Bombs cannot break the human spirit. Sheema Kermani dances at #LalShehbaz #Sehwan after bloodbath. My beautiful, resilient people #Pakistan pic.twitter.com/NFWf0ODj34 — Maliha Aqueel (@AQmaliha) February 20, 2017

"I felt sad, angry and fearless at the same time and nothing else seemed to matter except that the dhamaal must go on - the blood of those who died cannot flow in vain.

"We will protest, we will mourn but we will continue our age-old traditions; the sound of the drum and the beat of the feet will not stop."

Kermani explained that shrines, a blend of all subcontinental religions, are often targeted in Pakistan.

Musicians at the shrines have Hindu gods painted on their instruments to signify the syncretic culture of the holy places.

"This is a space where men and women from all classes, all backgrounds, different religions, irrespective of gender can come together as one. These shrines are also symbols of resistance and non-conformity and anti-establishment," Kermani said.

"They are under attack because they symbolise a defiance to established orthodox religion."

Shereena Qazi is on Twitter, Follow her on @shereenaqazi