IDEUMMMMMMM YOU ARE SO CUTEEEEEEE WAHHHHH （/TДT)/ ε=ε=(ノ≧∇≦)ノ
Porcelain anniversary: "20 years of marriage are called the porcelain anniversary. This twentieth wedding anniversary marks a symbolic stage in a couple's life, where each year is named after a material or a symbol. After 20 years of shared life, porcelain embodies the balance between delicacy and solidity."
The line at the beginning of this chapter: "A toast to the 20th anniversary. To the strength and beauty of white porcelain spun by master and servant."
Conclusion: They are married, Sebaciel is real and canon, and it is their 20th wedding anniversary. Congratulations Ciel and Sebastian. ⁄(⁄ ⁄·⁄ω⁄·⁄ ⁄)⁄
