Here’s why Sukuna wants to see Megumi’s evolution in Jujutsu Kaisen.
Megumi is one of the characters that has been close to Sukuna since the beginning of the anime, Well, he was the one who found Yuji Itadori with Satoru Gojo. Although at the beginning there is not much to say about the first contact with the King of Curses, when Yuji and his companions face the curse known as the Bearer of FingersSukuna manifests again taking control of the protagonist’s body.
Megumi here he has to face Sukuna and they have a brief fight where it is made very clear that Megumi is not prepared to fight against the King of Curses. At the time when Yuji is dying after having been left without the heart that Sukuna took from him, they both make a deal to stay alive and one of Sukuna’s sentences clarifies that he is very interested in Megumi Fushiguro, but without making anything clear.
This has generated many doubts among the viewersbut below, we leave you some things that explain what is happening about said character.
Why is Megumi Fushiguro so important to Sukuna?

Sukuna and Megumi have a bond in Jujutsu Kaisen
Although Sukuna has not revealed the exact plan he has in mind to re-emerge, Megumi could be the key to his goal for being the only current wielder of the Ten Type Shadow Technique. This cursed technique is part of the members of the Zenin Clan and one of the most powerful that have existed among shamans.
This would explain why Sukuna made a pact with Yuji to stay alive and see the progression of Megumi’s cursed technique, since if he manages to have adequate control over said power, he would be the only person capable of provide a stable body for Sukuna and thus he would stop being linked to a vessel like Yuji Itadori.
How does the Ten Type Shadow Technique work?

The Ten Type Shadow Technique is the key for Sukuna in Jujutsu Kaisen
The Ten Kinds of Shadow Technique is a cursed technique of offensive and defensive attacks that can only be controlled by people who inherit power in the Zenin Clan. The ability allows spawn, summon and control shikigamis They manifest themselves in the forms of animals of different types and have various functions during battles.
Megumi could be linked with Sukuna in the future

Sukuna wants to control Megumi in Jujutsu Kaisen
During the story, Sukuna greatly underestimates Yuji Itadoribut over time he realizes that it is actually more powerful than he expected, so much so that he could make Sukuna stay imprisoned in his body indefinitely after ingesting his cursed fingers bit by bit.
This is where Megumi’s cursed technique is important, and it is because she has the ability to summon up to ten different shikigamis, which are replaced by stronger ones when they are eliminated in combat, Megumi would fit like a glove for Sukuna’s plans. To be more specific, when one of the shikigamis is eliminated, it is subsequently replaced by a new one that inherits the cursed energy of the previousso when dying a much stronger one is manifested.
Therefore, the last shikigami left alive would be Accumulation of cursed energy of the above, which is summed up to a single shikigami of great power. This physical manifestation of the shikigami could be what Sukuna is looking for. create a body that works for youand at the same time be more powerful to enhance their abilities.
However, this could only come true if Megumi manages to control her power 100%and this would explain why Sukuna wishes to keep Megumi alive to see how her power evolves in the future.