However, I think the writers made it pretty clear that this was not their intent with the theme. So many people may be fooled into thinking the same thing is possible here and that the new partner is Isla's body. For example, a plot may revolve around accepting loss or acknowledging that things aren't permanent, only to have the climax completely undo any progression that has been made by, say, magically reviving a dead character, reigniting a lost love that both characters had accepted was over, etc. Unfortunately, many anime make poor choices and choose to shoot down their own themes. If someone is less mature or perhaps just very idealistic, they may root for some cosmic reunion between the two. If someone accepted this theme and understood the importance of it, they would likely believe the new partner is not Isla's body. The anime preaches an overarching theme of accepting things that cause you pain and moving on from them, cherishing the good experiences you had, and remembering what you learned.

A person's opinion about the ending reveals their maturity and how much they've developed so far in life. If you did not get it I really am sorry for you and at the same time I am wondering if when you guys watch an anime do you use your brains or only watch becouse it is a tear jerker or sth like that. This whole anime's main theme is about moving on. I think they replace Isla with the new OS just like they did to Andie, but that means Tsukasa just need to create new memories with her. Since someone said in the first couple episode that Terminal Service usually recycle their Giftias to cut cost down low. I have the same thought with you, it's gotta be Isla with new personality. Phew that was a lot but that is what I believe I think it is the most plausible theory. And the way that she smiled about him and michiru laughing together at the party let her be a little more at ease knowing that he wouldn't be alone and that they could potentially have something. And like Eru said to him at the carnival was that she didn't want to bring andie again because of the memories she had with Olivia.So I do believe that he will always love her, but he'll cherish her memory the most and not try to ruin what he had with her by trampling on it with trying to turn this giftia into someone she's not. I honestly think that it is a recycled isla, and coming to terms with islas' retrieval the memories he shared will never go away, but this new Giftia isn't isla and will never be isla, this one may not have any of the same mannerisms or tendencies, she may not be clumsy, she may not trip all the time, all the things he said he loved about her during the Ferris wheel, that's who he loved, this is probably nothing like her, except for appearance.

Plastic memories episode 13