Mohammed Islam and Masudur Rahman left a beach at Torquay and went with the girls to a nearby park where they took part in sex acts with them.
The two 19-year-olds from Tipton were on holiday with friends and were tempted by the girls because their strict upbringing meant they were inexperienced and immature. The girls were just 12 but lied about their ages and said they were 14 and were willing participants in everything that happened, Exeter Crown Court was told.
Both men had never been in trouble before and were respected members of their communities. One was a volunteer at a youth club and another about to start an economics and business degree at a university in London.
Islam, of Bevan Road, admitted two assaults and one sexual assault and Rahman, of Slater Street, admitted one assault and one sexual assault.
They were both jailed for two years in a Young Offender's Institution by Judge Francis Gilbert, QC and ordered to remain on the Sex Offenders' Register for life.
He told them: "You were both on a beach and started chatting to these two girls who were strangers. There was some flirting and you went with them to a rugby field near the railway station where they were both assaulted sexually.
"It was, to put it politely, a sordid sexual encounter. You both say they participated willingly and I accept that basis of plea.
"I accept they told you they were 14 but they were in fact 12 and they were complete strangers and even if they were 14 they were still under age and you were aged 18 or 19 at the time."
Miss Emily Pitts, prosecuting, said the two defendants were on holiday in Devon on September 5 last year and were on a beach in Torquay with a group of friends when they met the two girls.
She said:"They were both aged 12 but they told the defendants they were 14. When they went to a field nearby there was consensual sexual activity between them."
Miss Sarah Buckingham, defending Islam, said his strict upbringing had left him naïve and ill-equipped to cope with the encounter on the beach.
She said:"He is a young man of positively good character. He behaved in a way that was impulsive and immature. He feels he has brought great shame on himself and his family."
Mr Nicolas Gerasimidis, defending Rahman, passed up a reference from organisers at the Tipton Young Asian Women's Forum and said he had been a voluntary youth worker in his community.
"He is a young man of good character who at the time was immature and inexperienced and was unable to bridle his affections," he said.