Review of [Oshi No Ko]

I want to discuss the isekai genre. This review contains minor spoilers. There are numerous isekai anime, such as Oshi no Ko and Mushoku Tensei: Jobless Reincarnation. However, for many anime, the isekai premise is merely a narrative device to grant characters supernatural abilities, like self-awareness or sharp wit. For example, in Oshi no Ko, no explanation is provided for why the characters are reborn as Ai’s children, despite dying at different times and places. The show glosses over this, which feels unsatisfying and unreasonable. Even though isekai might not be the main focus of the show it's like forgeting their identity and being and starting allover again which i wonder why make it a reborn thing in the first place.

It’s frustrating how quickly some characters undergo drastic development in just a couple of episodes. Take the protagonist of Oshi no Ko, Aquamarine. Initially, he’s a calm, middle-aged doctor living peacefully in a small city, deeply dedicated to his patients. Suddenly, he transforms into an obsessive fan of a 16-year-old idol, partly because she reminds him of a former patient of the same age. This shift feels unsettling and borders on inappropriate. But that’s not even the character arc I’m focusing on. After his mother, Ai, dies, Aquamarine is consumed by thoughts of revenge and anguish. After a long stretch of little progress, he enters high school and becomes the quintessential TV trope: a charming, all-knowing teenage heartthrob who helps struggling girls—whom no one else seems to care about—and wins their affection. The revenge plot, meanwhile, unfolds in a lackluster manner, though that’s not the main focus of this review.

Then there’s the female character, reborn after dying from a severe illness, cancer, before reaching adolescence. At first glance, she seems like a soul who has endured immense hardship, finding solace only in her idol’s music. You might expect her to have a profound appreciation for life and its fleeting moments. But you’d be wrong. Upon reincarnation, she reverts to acting like a typical child, using the internet to attack her idol’s detractors and engaging in distasteful behavior, such as gloating to her brother about being breastfeed from their mother. Both siblings blush whenever they see their mother’s breasts, which reduces a mother’s love and affection to something perverse and fundamentally wrong.

In contrast, Mushoku Tensei: Jobless Reincarnation is the only anime that truly masters this challenging genre. It carries the protagonist through all stages of his life—keeping viewers connected to his journey—and never shies away from addressing his past life, even in the final episodes. This approach is truly commendable.

At the end all the progress in the first and seemingly best episode is just nothing but to let us now about the grudge carried on later on.

In the end, while Oshi no Ko ventures boldly into idol‑industry satire, its under‑explained rebirth premise and jarring character pivots undermine the emotional stakes it aspires to. By contrast, Mushoku Tensei’s steadfast commitment to a cohesive life‑arc demonstrates how an isekai can both justify its fantastical mechanics and sustain genuine character growth. Going forward, the genre will only deepen its impact when creators fuse rigorous world‑building with the long‑game storytelling that keeps viewers invested from first rebirth to final reckoning. Cause you can't just omit a person's personality just for the sake of the show and except a emotional investment from viewers.