无牵无挂

tā men ràng rén míng xiǎn gǎn jué shì yī duì wú qiān wú guà zhǐ qiú cháng xiāng sī shǒu de fū qī

他们让人明显感觉是一对无牵无挂，只求长相厮守的夫妻。

They certainly gave the impression of a carefree couple who delighted in each other's company.