As we know, Loki wanted to marry Lola. But Lola rejected him and ran off. Big Mom tried to give Loki Chiffon instead, but he didn’t take her.
What this means is that shockingly, Loki wasn’t merely attracted to Lola for her appearance. After all of that was the case, then he would have just married Chiffon.
Rather he must have fallen in love with her personality. Lola was a free spirited pirate woman. More than that she was the first of Big Mom’s children to defy Big Mom’s wishes.
Given how we know Loki ultimately killed Harold and took his Devil Fruit, I think it could be the case that Loki empathized with Lola. I think Harold could have been a a truly horrible person, just like Big Mom. Loki wanted to disobey Harold just like how Lola rebelled against Big Mom.
We know that the Buccaneers are part giant, yet the World Government hunted them all to death. Where was Harold in all of this? Why didn’t Harold protect his giant brethren? Had he given Buccaneers sanctuary in Elbaf, none of them would have been killed or enslaved.
I think it’s very likely that Harold was a corrupt and evil despot. He had immense power, ruling elbaf and having the legendary fruit, yet he only used it for selfish purposes. When the World Government started to persecute the Buccaneers, I think Harold probably sold out the Buccaneers for his own benefit.
Ultimately, I think Loki killed Harold so he could use the legendary fruit to fulfill Joy Boy’s will. That is, to go to war with the World Government.
*Theory by Monkey D Theories