Definitions according to Wikipedia (definitely not the be all end all for definitions:
Asexuality is a sexual orientation describing individuals who do not experience sexual attraction[1][2] or do not have interest in or desire for sex.
Heterosexuality refers to sexual behavior and attraction to people of the opposite sex, or to a heterosexual orientation.
Heteroflexible/ Bi-curious is a term used to refer to someone who does not identify as bisexual or homosexual but feels or shows some curiosity in a relationship or sexual activity with someone of the same sex.
Bisexuality refers to sexual behavior with[1] or physical attraction to people of both genders (male and female), or a bisexual orientation.
Pansexuality is a sexual orientation characterized by the potential for aesthetic attraction, romantic love, or sexual desire for people, regardless of their gender identity or biological sex.
Queer has traditionally meant odd or unusual, though modern use often pertains to LGBT (gay, lesbian, bisexual, transgender, intersex) people.
Homosexuality refers to attraction and/or sexual behavior between people of the same sex, or to a sexual orientation.
So what is the difference between pansexuality and queer? And what is a person who will have sex with males and females but doesn't want to have a relationship with the same gender as their own?