Question: Peter Straker had a personal relationship with the British singer who was the lead vocalist for which group?

Context paragraphs:
I'm Going Slightly Mad: "I'm Going Slightly Mad" is a song by the British rock band Queen.  Written by Freddie Mercury but credited to Queen, with uncredited lyrical contributions by Peter Straker, it was released as the second single from the band's 1991 album "Innuendo".  The lyrics and the accompanying music video project the song as quirky, humorous and light-hearted.  The song also features a slide guitar solo performed by Brian May.  John Deacon's bass is tuned down to a low B.

Stanley O. Gaines: Stanley O. Gaines, Jr. is a Social Psychologist and Senior Lecturer in the School of Social Sciences at Brunel University.  Gaines is the lead author of "Culture, Ethnicity, and Personal Relationship Processes", published by Routledge in 1997 (ISBN  ).

Kanchan Wali-Richardson: Kanchan Wali-Richardson (born 1990) is an American interdisciplinary visual artist who currently lives and works in Nashville, Tennessee.  The themes of her work primarily center around her personal relationship to the politics, religious implications, and sociality of environmental issues.  In 2014–2015, Wali-Richardson was selected as a participant in the Fulbright Program, receiving a research grant to India to work on a project titled "Holy City Stairs: The Ghats of Varanasi."  She has participated in solo and group exhibitions in Los Angeles and New York.

Donna McKechnie: Donna McKechnie (born November 16, 1942) is an American musical theater dancer, singer, actress, and choreographer.  She is known for her professional and personal relationship with choreographer Michael Bennett, with whom she collaborated on her most noted role, "Cassie" from the musical "A Chorus Line", for which she earned the Tony Award for Best Actress in a Musical in 1976.  She is also known for playing Amanda Harris/Olivia Corey on the Gothic soap opera, "Dark Shadows" from 1969 to 1970.

Peter Straker: Peter Straker (born 7 November 1943) is a Jamaican born singer and actor, best known for appearances in "Doctor Who" (in the 1979 serial "Destiny of the Daleks") and the 1985 ITV series "Connie".  He also had a long-standing professional and personal relationship with Freddie Mercury.

A Deeper Kind of Slumber: A Deeper Kind of Slumber is the 1997 Century Media Records release by Swedish band Tiamat.  Featuring female background vocals by Birgit Zacher (Moonspell, Angel Dust) and experimentation with a variety of influences, the album marked the group's first complete withdrawal from both death metal and conventional heavy metal, following their 1994 release, "Wildhoney".  It was also the first production after their relocation to Germany, and was written almost entirely by founder/lead songwriter Johan Edlund.  Much of the music had reflected on Edlund's personal relationship with drugs, creative differences within the band as well as an interpersonal relationship.

Freddie Mercury: Farrokh "Freddie" Mercury (born Bulsara; 5 September 1946 – 24 November 1991) was a British singer, songwriter and record producer, known as the lead vocalist of the rock band Queen.  He was known for his flamboyant stage persona and four-octave vocal range.  Mercury wrote numerous hits for Queen, including "Bohemian Rhapsody", "Killer Queen", "Somebody to Love", "Don't Stop Me Now", "Crazy Little Thing Called Love", and "We Are the Champions".  He led a solo career while performing with Queen, and occasionally served as a producer and guest musician for other artists.

Chris Pérez: Christopher Gilbert "Chris" Pérez (born August 14, 1969) is an American guitarist, songwriter and author best known as lead guitarist for the Tejano band Selena y Los Dinos.  He married the frontwoman of the group, Selena, on April 2, 1992.  Pérez grew up in San Antonio, Texas as one of two children of Gilbert Pérez and Carmen Medina.  In 1986, he joined Shelly Lares' band.  By the late 1980s, Pérez was reputed among Tejano musicians for his guitar skills.  This caught A.B. Quintanilla's attention; at the time, Quintanilla was seeking another guitarist for the band he produced, Selena y Los Dinos.  Between one and two years after Pérez joined the band, he and Selena began a personal relationship.

To Ramona: "To Ramona" is a folk waltz written by Bob Dylan for his fourth studio album, "Another Side of Bob Dylan".  The melody is taken from traditional Mexican folk music.  "To Ramona" is also a nod to Rex Griffin's 1937 song "The Last Letter".  The song is one of several on the album to highlight the more personal, less political, side of Dylan's songwriting that would become more prominent in the future.  The song also makes allusions to Dylan's personal relationship with fellow folk singer Joan Baez, at the time of its composition and subsequent release.  It is another example of the G, G6, G7 harmonic motif Dylan uses pervasively on the record.

Evelyn Frechette: Mary Evelyn "Billie" Frechette (September 15, 1907 – January 13, 1969) was an American Menominee singer, waitress, convict, and lecturer known for her personal relationship with the bank robber John Dillinger in the early 1930s.

Supporting paragraphs: Peter Straker Freddie Mercury
Answer: Queen