Plenty of anime are known for their iconic opening and ending themes, but the insert songs in a series can be just as memorable. The right song at the right time can even leave viewers bawling before they even realize it's happening.

Here are a few of the saddest anime songs that do just that, and what makes them so emotional.

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Demon Slayer: "Kamado Tanjiro no Uta"

Tanjiro Using Fire Attack In Demon Slayer Anime

Demon Slayer is jam-packed with action, endearing characters and a soundtrack that slaps. One song in particular does a great job of communicating protagonist Kamado Tanjiro's sorrow and determination. "Kamado Tanjiro no Uta" appears in Episode 19 of Season 1 when he fights Rui, Lower Five of the Twelve Kizuki.

Tanjiro recognizes he may not survive the battle after his sword is shattered. While "Kamado Tanjiro no Uta" plays, he recalls the peaceful life he and his family had once lived. The sentimental moment swells as Tanjiro remembers his father performing the Hinokami Kagura, eventually channeling that memory into fuel for battle. Likewise, the song becomes more impassioned to mirror the strengthening of Tanjiro's resolve. His story is heartbreaking, and "Kamado Tanjiro no Uta" emphasizes how his undying love and devotion to his family gives him strength when he needs it most.

Related: Demon Slayer: Why [SPOILER] Will Be the Strongest Foe the Trio’s Faced Yet

Fruits Basket (2019): "Umareru Negai"

Fan Favorite Fruits Basket Characters

With themes of grief, loss and the legacy of intergenerational trauma, Fruits Basket can easily trigger the waterworks. The heartfelt series received an anime reboot in 2019, with the story's tender, tear-jerking quality remaining intact. As Tohru Honda spends more time with the Sohmas, the moments where she is alone stand out.

"Umareru Negai" underlines these moments of solitude. In Episode 5 of Season 1, Tohru is disheartened when she learns that she can move back in with her grandfather, breaking down at the possibility of her friendship with the Sohmas disappearing. The song's gentle, resonant melody highlights how, no matter how resilient Tohru may appear, the thought of being alone still scares her. With lyrics about healing and moving forward, "Umareru Negai" is a touching reminder that even in the darkest of times, no one, including Tohru, is ever truly alone.

Related: Fruits Basket -Prelude- Reveals New Trailer, Poster Art

Anohana: The Flower We Saw That Day - "I Left You"

Menma from Anohana: The Flower We Saw That Day crying as the sun sets behind her

While only 11 episodes long, Anohana: The Flower We Saw That Day packs an emotional wallop that viewers won't easily forget. The song "I Left You" intensifies the already powerful emotions in this coming-of-age story.

Protagonist Jintan suddenly begins to see his childhood friend Menma, even though she's been dead for five years. He reunites their friend group to try and help Menma pass on, which means all of them must confront their guilt and grief. As they come to terms with the events leading up to her accident, they can now accept and mourn the passing of their dear friend. When Jintan carries Menma on his back in the series finale, she slowly disappears as she passes on. "I Left You" plays throughout Menma's tearful departure, and its lyrics about acceptance and moving on perfectly accentuate the anguish of saying goodbye to a loved one.

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Fullmetal Alchemist: Brotherhood - "Requiem for a Brigadier General"

Maes Hughes and his daughter (Fullmetal Alchemist)

The story of Edward and Alphonse Elric is as filled with sorrow as it is action-oriented. Both anime adaptations have their share of catchy opening and ending themes, as well as insert songs bound to tug at a fan's heartstrings, like Fullmetal Alchemist: Brotherhood's "Requiem for a Brigadier General".

Lieutenant Colonel Maes Hughes is one of the many friends Ed and Al make along their journey to restore the latter's body. Hughes quickly makes his way into viewers' hearts with his friendly demeanor and comically exuberant displays of love for his wife and daughter. As such, his sudden death in Episode 10 leaves a mark on characters and fans alike. "Requiem for a Brigadier General" plays during the nearly silent funeral procession, subdued enough to fit with the event's somberness while its crescendos parallel the crumbling of the attendees' cool facades. Once Elicia, Hughes' daughter, begins to cry out, there's no holding back the tears.

The soundtrack to an anime can make a lasting impression on fans. Some songs are so linked to the sadness of a moment that they're guaranteed to leave audiences scrambling for a tissue, no matter how many times they've heard it.

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