Elalude Grimwald is a character from the anime and light novel series That Time I Got Reincarnated as a Slime. He is an elf noble of high standing, holding the title of Grand Duke. He is a member of the Thirteen Royal Families, the ruling houses of the Sorcery Dynasty of Sarion, and serves as the uncle to the young emperor, Elmesia El Ru Sarion. His family relations extend further; he is the father of a daughter named Elen, also known as Elyune, and has other relatives including a brother named Sarion Grimwald, a sister-in-law named Sylvia, and a mother named Ellis.

In terms of personality, Elalude is depicted as a competent and reliable statesman who is heavily relied upon in both public and private matters by his niece, the emperor. Despite being much younger than Elmesia and often treated like a child by her, he wields significant authority. He has a tendency to be a loving, or perhaps overprotective, father to his daughter Elen, going so far as to assign the nation's mage corps to act as her personal guards. His political acumen is sharp, but he is not without a playful or arrogant streak; he maintains a very close friendship with King Gazel Dwargo of the Dwarf Kingdom, a relationship characterized by their ability to freely insult each other and engage in banter.

His core motivations are rooted in the prosperity and security of the Sorcery Dynasty of Sarion, combined with a strong protective instinct for his family, especially his daughter. In his role as a key figure in Sarion's government, he is responsible for making high-level diplomatic decisions and securing beneficial alliances. His actions demonstrate a desire to assess potential allies carefully and pragmatically, ensuring that any relationship serves his nation's long-term interests, though his methods can sometimes be aggressive in pursuing short-term gains.

Elalude plays a significant role as a political actor on the international stage. In the sixth volume of the light novel, he is entrusted with the full authority of the nation during a critical period. He uses a homunculus as a vessel to transfer his consciousness for safe travel and sends it to the Jura Tempest Federation to assess the newly proclaimed Demon Lord Rimuru Tempest. During the subsequent Human-Monster Conference, he carefully observes the proceedings and the other political leaders. After a thorough evaluation, he formally recognizes Rimuru as a trustworthy individual and secures a friendship agreement between Sarion and the Jura Tempest Federation, becoming a key member of the coalition Rimuru was building to counter external threats.

His key relationships are central to his character. Beyond his bond with King Gazel and his dynamic with Emperor Elmesia, his relationship with Rimuru evolves from cautious observer to trusted ally. His interaction with Fuze, the representative of the Kingdom of Blumund, also shows his analytical nature, as he questions Fuze deeply about his motivations for supporting the monster nation. His relationship with his daughter, Elen, highlights a personal, more sentimental side to his character, contrasting with his public persona as a shrewd politician.

Elalude shows some development over the course of the story. While he is an experienced and astute leader, he is not infallible. He is reprimanded by Emperor Elmesia for negotiating the construction of a highway with the Jura Tempest Federation in a manner that placed the entire financial burden on the other party. From a long-term perspective, the emperor considered this a poor decision that could harm future relations. Demonstrating an ability to learn and adapt, during subsequent negotiations for the installation of a magic railway, he proposed that his own country share the financial burden, showing a more balanced and diplomatic approach.

Regarding notable abilities, Elalude is a skilled wizard. He is capable of casting powerful, high-tier magic, including an extremely potent combustion spell that can be used against entire armies. His most distinctive ability is his means of travel and diplomacy. He typically operates by using a homunculus body, an artificial construct, into which he transfers his own consciousness. This allows him to conduct diplomatic missions and attend international meetings without risking his physical person. His appearance is noted as being distinguished, with blonde hair that frames his face and narrow green eyes.