The reading せいちをきわめる (seichi o kiwameru) combines the On'yomi 精 (sei) and 緻 (chi). 緻 (chi) is a less common kanji meaning 'delicate' or 'meticulous', and is often misread as つち or し. This phrase describes something that is extremely elaborate, intricately detailed, or exquisitely crafted to the highest degree.

精（セイ）緻（チ）のOn'yomiに、「きわめる」が続きます。「緻」は「こまかい」を意味し、誤読しやすい漢字です。非常に細かく、手の込んだ作りや表現を指します。