Recently I've been picking up anime series left and right that are below 10 episodes long. They end too soon for my liking but every single one so far has made as deep an impression as those over 10 episodes long. Triangle Heart is an OVA that is only 4 episodes long that tells the story of Kyoya Takamachi.
Years ago, professional bodyguard Shirō Fuwa and his client Albert Crystela were killed by a terrorist organization that bears the symbol of a clover leaf. Albert's daughter Fiasse blamed herself, but then grew closer to the Fuwa (now Takamachi) children, Kyōya and Miyuki, and decided to use her gift of singing to help the world. But now that they have grown up, Fiasse herself is being targeted by the same organization. Kyōya and Miyuki, swearing to protect Fiasse, become professional bodyguards like their father.
Both of the Takamachi siblings are experts in swordsmanship and through this, they protect Fiasse. At times conflicting with Elise her gun wielding bodyguard that shares a dark secret with Kyoya, the tension in the 4 episodes mount palpably.
With a nice wrap up, Triangle Heart is a pretty decent anime at only 4 episodes. One should try out these shorties now and then

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