Hii

Robin Hood and Loki predate any of the phantom thieves' personas. What is Robin Hood? An honorable thief. Basically a counterpart to Arsene's gentleman thief.

Even more interesting is Loki. The rest of the Thieves only get their persona upgraded to a 'mythological trickster' upon their second awakening. From a purely gameplay perspective, you spend time with Joker's friends in order to give them stronger personas (grind and reward).

But Loki is known as a trickster god in Norse mythos. He is already a mythological trickster. From the beginning, Akechi was already what Joker needed him to be.

And then there's Arsene, who is so blatant that he's the reason I clocked shuake's soulmatism from the moment Joker awoke him (literally in kamoshida's palace I figured Joker would meet a detective rival in the story). Basic Arsene Lupin lore is that the character was written by author Maurice Leblanc as the 'French response' to Sherlock Holmes (for copyright reasons it's herlock sholmes).

Arsene exists because of Sherlock. So of course Joker is so obsessed with Akechi in-canon. That's literally what his soul is built for.

There's another layer to this.

The name "Goro Akechi" is inspired by the Japanese detective character "Kogoro Akechi" written by Japanese author Edogawa Ranpo (this is also the reason I clocked akechi as the rival the moment he introduced himself, I did my time in the BSD fandom). Kogoro Akechi is a detective character heavily inspired from Sherlock Holmes.

So Joker's soul is a thief character written to rival Sherlock Holmes, while Akechi's name comes from a detective character written to emulate Sherlock Holmes. They've been searching for each other from the very beginning.

Ren and Morgana after engine room incident

(OG image under the cut)

the evil mirror that turns you gay(er)

(caption shamelessly stolen from @shiroselia who hasn't played silksong but still summed it up beautifully)