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perfect beauty with no trace of artifice; flawless
彼女の演技は天衣無縫で観客を魅了した。
Her performance was flawless and captivated the audience.
天衣無縫な笑顔が周囲を和ませた。
Her natural, artless smile put those around her at ease.
天衣無縫の計画が見事に成功を収めた。
The flawless plan achieved remarkable success.