Ashok Kumar, 20, and Jyoti, 18, were found dead at the tourist complex in Sohna, 26 km from Gurgaon city.
Ashok hailed from Gudana village near Pataudi while Jyoti was from Kheri Khumar village in Jhajjar district. Both were unmarried.
The duo had arrived at the hotel around 8.30 p.m. Saturday and booked a room for the night.
"They were relatives of each other and in love. Both consumed salfas tables. They also left a suicide note blaming no one for their taking the extreme step," Anil Kumar, chief of Sohna police station, told IANS.
The one-line suicide note, having signatures of the deceased, read: "Hum apni marji se mar rahe hain (we are dying as per our own choice)."
Jyoti was a B.A. 1st year student at a Rohtak college while Ashok was a school dropout.
"Ashok had booked room no.1 on the driving licence identity card of his elder brother. They had called a waiter at 10.30 p.m. and asked for some water. They also had not ordered dinner," said police.
Ashok's body was found on the bed while that of Jyoti was lying near the bushes outside the room.
The bodies were handed over to their respective family members after post-mortem.