Valmiki Ramayana Yuddha Kanda Sarga 32 Shloka 32
Original Shlokaशिरसामेशिरश्चास्यकायंकायेनयोजय । रावणानुगमिष्यामिगतिंभर्तुर्महात्मनः ।।6.32.32।।
1 source checked for this shloka
रावण Ravana, मेशिरसा my head, अस्य with his, शिरः head, कायेन body, कायम् with his body, येजय join, महात्मनः great soul, भर्तुः husband, गतिम् way, अनुगमिष्यामि will follow.
"O Ravana! Join my head with his and my body with his body. I will follow him in the same way."