pro cannibalism individual

First, I should probably explain why I think Seodore is the Lime Azure:

We know the Lime Azure went missing alongside Theodore in the sinking of the Polaris. (record 4)

The rock is gone, but Seodore returns.

He also makes mention of his pieces being used during the chainsaw incident - we know that both Rangiri and Mutei have used pieces of That Damn Rock in Rangiri's Medicine and Mutei's Factor Artifacts respectively, and both of those were done BEFORE the chainsaw incident happened. We know this because a) Rangiri is Unstable after the chainsaw incident, and b) Mutei is just Gone.

the quotes below establish that Aescula's Medicine had the Lime Azure in it (record 7)

These lines establish the artifacts as having pieces of the Lime Azure in them (record 7) (DLC credits) (Artbook) (interlude report 5), and establishes them as created by Mutei ("Dr. Martin")

 [Mutei has] left his descendants a rainbow fountain pen, an emerald lens, and a ruby knife.

The pieces were from Seodore.

We can also establish this from the fact that the artbook highlights the Lime Azure as the catalyst for Seodore's "Respawn" ability. The colored sections were originally censored. (TL HERE)

Respawn (Real Name: Continue) Type: Persistent Ability Source: Tag/Player Character Catalyst: Lime Azure Level: Impossible to measure Seodore might not have Empyrean cells himself, but he has regenerative abilities and durability very close to that of Empyrean lifeforms. However, even that has limits, and there are injuries that result in death for him. This ability activates automatically when Seodore either 1) dies or 2) gets into a situation he can’t escape from. When this ability activates, it restores him to his most recent safe point. The restored Seodore is the same person, with the same memories and awareness of all the events that have transpired. Sometimes this ability activates and rewinds time to before the incident that killed him occurred, and sometimes it simply makes the body vanish and revives him but doesn’t change the situation itself. His earrings are also recognized as part of him, so they disappear with his corpse and appear back on him when he respawns, just like the rest of what he’s wearing. 

(for more about what I think "player character" means, I talk about it here. That's off topic for now, though)

Seodore mentions a handful of different times that he doesn't age, he doesn't change physically, it just is stuck at as he was at 25. (from the artbook).

[N’s Attached Note: Could it be: [Seodore's] hair doesn’t grow either?]

It's not just that Seodore lost his memories; it's that the original person who HAD those memories is dead, and Seodore is a new consciousness, in that same body.

From the Databook Timeline (TL HERE). The colored sections were originally censored.

9/29/1886: Born: Theodore Riddle 4/15/1912: Incident: Polaris cruise ship sinks. Theodore Riddle is shipwrecked. 5/25/1912: Seodore Riddle returns. Born: Seodore Died: Theodore

From the DLC credits, we get this line. SOMETHING happened on the Polaris (the details of which are unclear).

I know in the interlude reports and a few other places, they describe it as memory loss, but Seodore makes the distinction very clear and actively rejects seeing himself as "Theodore Riddle". For all intents and purposes, Theodore Riddle is dead. Seodore is the one who's here.

I think the chainsaw incident changed things for seodore too, but as that's more speculative, i'll leave that out of this response ^^; The only thing I'll note here is that in the databook timeline, the chainsaw incident is described as "Seodore's Awakening." I personally think this refers to Seodore's awareness of the nature of the world/the edges of the "screen". This is heavily speculation, though. A lot of theorycrafting is putting together several ambiguous lines that come together to imply something; we can't say much for sure because we simply don't know.