Loki is an admirer of Xebec, and the two characters are quite similar. Xebec's flashbacks in Loki's flashbacks show Loki being more closely related to Xebec than to Teach.
The relationship between Teach and Xebec is similar to that of Ace and Roger, whose personality is inherited from Roger's, Luffy, who is Garp's son. Garp himself was Roger's friend.
This is similar to Xebec and Loki, whose character is the son of his friend, Harald.
Ace and Teach both ultimately lost because they possessed traits that deviated from their respective fathers, ultimately leading to the end of the story with Joy Boy and David Jones.
The relationship between Teach and Xebec is similar to that of Ace and Roger, whose personality is inherited from Roger's, Luffy, who is Garp's son. Garp himself was Roger's friend.
This is similar to Xebec and Loki, whose character is the son of his friend, Harald.
Ace and Teach both ultimately lost because they possessed traits that deviated from their respective fathers, ultimately leading to the end of the story with Joy Boy and David Jones.

